As filed with the Securities and Exchange Commission on March 28, 2008

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

CELL THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Washington	2834	91-1533912
(State of other jurisdiction of incorporation or organization)	(Primary Standard Industrial Classification Code Number)	(I.R.S. Employer Identification No.)

501 Elliott Avenue West, Suite 400

Seattle, Washington 98119

(206) 282-7100

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

James A. Bianco, M.D.

President and Chief Executive Officer

Cell Therapeutics, Inc.

501 Elliott Avenue West, Suite 400

Seattle, Washington 98119

(206) 282-7100

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:

Karen A. Dempsey, Esq.

Donna Cochener, Esq.

Heller Ehrman LLP

333 Bush Street

San Francisco, California 94104

(415) 772-6000

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this registration statement as determined by the selling securityholders.

If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ¨

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  x

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a post effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ¨

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ¨

CALCULATION OF REGISTRATION FEE

Title of Each Class of Shares To Be Registered	Amount to be Registered (1)	Proposed Maximum   Offering Price Per   Unit (2)	Proposed Maximum   Aggregate Offering Price (2)	Amount of Registration Fee
Common Stock, no par value	8,920,205(3)(4)	$0.695	$  6,199,542(5)	$  31.96(6)
5.75% Convertible Senior Notes due December 15, 2011	$23,250,000(6)		$23,250,000	$913.72
Total			$29,449,542	$945.69

(1) Pursuant to Rule 416 of the Securities Act, such number of shares of common stock registered hereby shall include an indeterminate number of shares of common stock that may be issued in connection with a stock split, stock dividend, recapitalization or similar event, including, without limitation, such indeterminable additional shares as may become issuable from time to time upon conversion of the notes as a result of the anti-dilution provisions in connection with the notes.

(2) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(o) under the Securities Act of 1933 and exclusive of accrued interest and distributions, if any.

(3) The shares of common stock that are being registered are the shares of common stock issuable upon conversion of the notes at the conversion rate of 333.333 shares per each $1,000 principal amount of notes, subject to adjustment in certain circumstances, which is equivalent to an initial conversion price of $3.00 per share of common stock.

(4) Includes 7,749,992 shares of common stock issuable upon conversion of the notes.

(5) Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) under the Securities Act, based upon the average of the high and low sales prices of the registrant’s common stock, as reported on the NASDAQ Global Market on March 27, 2008.

(6) Pursuant to Rule 457(i), no additional filing fee is payable with respect to the 7,749,992 shares of common stock issuable upon conversion of the notes because no additional consideration will be received in connection with the exercise of the conversion privilege.

(7) Represents the aggregate principal amount of the notes issued by the Registrant.

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED March 28, 2008

PROSPECTUS

$23,250,000 5.75% Senior Convertible Notes and

8,920,205 Shares of Common Stock

We issued the notes and shares of common stock offered by this prospectus in a private placement in December 2007. This prospectus will be used by selling securityholders to resell their notes, shares and the common stock issuable upon conversion of the notes. We will not receive any proceeds from this offering.

The selling securityholders may offer and sell their shares in public or private transactions, or both. These sales may occur at fixed prices, at market prices prevailing at the time of sale, at prices related to prevailing market price, or at negotiated prices. The selling securityholders may sell shares through underwriters, broker-dealers or agents, who may receive compensation in the form of discounts, concessions or commissions from the selling securityholders, the purchasers of the shares, or both. See “Plan of Distribution” for a more complete description of the ways in which the shares may be sold.

Holders may convert the notes into shares of our common stock at any time before their maturity unless we have previously redeemed or repurchased them. The notes will be due on December 15, 2011. The conversion rate is 333.333 shares per each $1,000 principal amount of notes, subject to adjustment in certain circumstances. This is equivalent to an initial conversion price of $3.00 per share.

We will pay interest on the notes on June 15 and December 15 of each year. The first interest payment will be made on June 15, 2008. The notes rank pari passu in right of payment with all of our existing and future senior indebtedness, including our 6.75% Convertible Senior Notes due 2010, 7.5% Convertible Senior Notes due 2011, 9% Convertible Senior Notes due 2012 and rank senior in right of payment to our currently outstanding 5.75% Convertible Senior Subordinated notes due June 2008, 5.75% Convertible Subordinated Notes due June 2008 and 4% Convertible Senior Subordinated Notes due 2010.

The notes are not listed on any securities exchange or included in any automated quotation system. The notes are eligible for trading on PORTAL, a NASDAQ Institutional Market. Our common stock is quoted on the Nasdaq Global Market and on the MTA in Italy under the symbol “CTIC.” On March 27, 2008, the last reported sale price of our common stock on the Nasdaq Global Market was $0.71.

Investing in our common stock involves a high degree of risk. See “ Risk Factors” beginning on page 8 of this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is March 28, 2008

TABLE OF CONTENTS

	Page
About This Prospectus	ii
Special Note Regarding Forward-Looking Statements	ii
Summary	1
Risk Factors	8
Use of Proceeds	25
Description of Capital Stock	25
Description of Notes	27
Selling Securityholders	38
Plan of Distribution	40
Legal Matters	42
Experts	42
Where You Can Find More Information	43
Documents Incorporated by Reference	43

No dealer, salesperson or other person is authorized to give any information or to represent anything not contained in this prospectus or any prospectus supplement. You must not rely on any unauthorized information or representations. This prospectus is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. The information contained in this prospectus or any applicable prospectus supplement is current only as of its date, and the information contained in any document incorporated by reference in this prospectus is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus or any prospectus supplement or any sale of a security.

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ABOUT THIS PROSPECTUS

This prospectus relates to the resale of up to $23,250,000 in aggregate principal amount of our 5.75% Convertible Senior Notes due 2011 and up to 8,920,205 shares of our common stock by the selling securityholders, which includes the 7,749,992 shares isusable upon conversion of the notes. The notes and 1,170,213 shares not issuable upon conversion of the notes were issued to the selling securityholders in a private placement in December 2007. We will not receive any proceeds from the potential sale of the notes or shares offered by the selling securityholders.

This prospectus constitutes part of the registration statement of Form S-3 filed with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”), utilizing a “shelf” registration or continuous offering process. It omits some of the information contained in the registration statement and reference is made to the registration statement for further information with regard to us and the securities being offered by the selling securityholders. Any statement contained in the prospectus concerning the provisions of any document filed as an exhibit to the registration statement or otherwise filed with the Securities and Exchange Commission is not necessarily complete, and in each instance, reference is made to the copy of the document filed.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

In addition to the other information contained or incorporated by reference in this prospectus supplement and accompanying prospectus, you should carefully consider the risk factors contained in and incorporated by reference into this prospectus supplement and accompanying prospectus when evaluating an investment in our notes and common stock into which the notes are convertible. This prospectus supplement and accompanying prospectus and the documents incorporated by reference into this prospectus supplement and accompanying prospectus include “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (“Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (“Exchange Act”). All statements other than statements of historical fact are “forward-looking statements” for purposes of these provisions, including:

• any statement regarding the performance, or likely performance, or outcomes or economic benefits of any licensing or other agreement, including any agreement with Novartis Pharma AG or its affiliates, including whether or not such partner will elect to participate, terminate or otherwise make elections under any such partnership agreement or whether any regulatory authority required to enable such agreement will be obtained;

• any projections of revenues, operating expenses or other financial items;

• any statements of the plans and objectives of management for future operations;

• any statements concerning proposed new products or services;

• any statements regarding future operations, plans, regulatory filings or approvals;

• any statements on plans regarding proposed or potential clinical trials or new drug filing strategies or timelines;

• any statements concerning proposed new products or services, any statements regarding pending or future mergers or acquisitions; and

• any statements regarding future economic conditions or performance, and any statement of assumptions underlying any of the foregoing.

In some cases, forward-looking statements can be identified by the use of terminology such as “may”, “will”, “expects”, “plans”, “anticipates”, “estimates”, “potential”, or “continue” or the negative thereof or other comparable terminology. There can be no assurance that such expectations or any of the forward-looking statements will prove to be correct, and actual results could differ materially from these projected or assumed in the forward-looking statements. Our future financial condition and results of operations, as well as any forward-looking statements, are subject to inherent risks and uncertainties, including, but not limited to, the risk factors set forth in this prospectus. All forward-looking statements and reasons why results may differ included in this prospectus are made as of the date hereof, and we do not intend to update any such forward-looking statement or reason why actual results might differ.

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SUMMARY

The following summary highlights information contained elsewhere, or incorporated by reference, in this prospectus. The following summary does not contain all the information that you should consider before investing in our common stock. You should read this entire prospectus carefully, including the documents that we incorporate by reference into this prospectus. Unless otherwise indicated, “CTI,” “Company,” “we,” “us,” “our” and similar terms refer to Cell Therapeutics, Inc. and its subsidiaries.

Our Company

We develop, acquire and commercialize novel treatments for cancer. Our goal is to build a leading biopharmaceutical company with a diversified portfolio of proprietary oncology drugs. Our research, development, acquisition and in-licensing activities concentrate on identifying and developing new, less toxic and more effective ways to treat cancer.

On December 21, 2007, we completed our acquisition of the U.S. development, sales and marketing rights to the radiopharmaceutical product Zevalin^® (Ibritumomab Tiuxetan), or Zevalin, from Biogen Idec Inc., or Biogen, pursuant to an Asset Purchase Agreement. Zevalin was the first radioimmunotherapy approved by the U.S. Food and Drug Administration, or FDA. It was approved in 2002 to treat patients with relapsed or refractory low-grade, follicular, or B-cell non-Hodgkin’s lymphoma, or NHL. The assets acquired included the Zevalin FDA registration, FDA dossier, U.S. trademark, trade name and trade dress, customer list, certain patents and the assignment of numerous contracts. Additionally, we entered into a seventy-eight month supply agreement with Biogen to manufacture Zevalin for sale in the United States as well as a security agreement providing Biogen a first priority security interest in the assets purchased in the transaction. We made an upfront payment to Biogen of $10.1 million at the time of closing and are also responsible for up to $20 million in contingent milestone payments based on positive trial outcomes and FDA approval for label expansion. We are also obligated to make additional royalty payments based on net sales of Zevalin.

On July 31, 2007, we completed our acquisition of Systems Medicine, Inc., or SM, a privately held oncology company, in a stock for stock merger, valued at $20 million. SM stockholders can also receive a maximum of $15 million in additional consideration (payable in cash or stock at our election, subject to certain Nasdaq limitations on issuance of stock) upon the achievement of certain FDA regulatory milestones. Under the agreement, SM became Systems Medicine LLC and operates as a wholly owned subsidiary of CTI. SM holds worldwide rights to use, develop, import and export brostallicin, a synthetic DNA minor groove binding agent that has demonstrated anti-tumor activity and a favorable safety profile in clinical trials in which more than 200 patients have been treated to date. SM currently uses a genomic-based platform to guide development of brostallicin; we expect to use that platform to guide development of our licensed oncology products in the future. SM also has a strategic affiliation with the Translational Genomics Research Institute, or TGen, and has the ability to use TGen’s extensive genomic platform and high throughput capabilities to target a cancer drug’s “context-of-vulnerability,” which is intended to guide clinical trials toward patient populations where the highest likelihood of success should be observed, thereby potentially lowering risk and shortening time to market.

We are developing paclitaxel poliglumex, which we have previously referred to as XYOTAX, for the treatment of non-small cell lung cancer, or NSCLC, and ovarian cancer. Based on feedback related to our European marketing application submission, we intend to rebrand XYOTAX and therefore now refer to it by its generic name, paclitaxel poliglumex. As announced in March and May 2005, our STELLAR 2, 3, and 4 phase III clinical studies for paclitaxel poliglumex did not meet their primary endpoints of superior overall survival. However, we believe that the reduction in toxicities coupled with superior convenience and less medical resource utilization demonstrated in the STELLAR 4 phase III clinical trial merits consideration for approval as single agent therapy for patients with advanced NSCLC who have poor performance status, or PS2. Currently there are no drugs approved for patients with PS2 NSCLC. On March 4, 2008, we submitted a Marketing Authorization Application, or MAA, to the European Medicines Agency, or EMEA, for first-line treatment of patients with advanced NSCLC who are PS2, based on a non-inferior survival and improved side effect profile which we believe was demonstrated in our STELLAR clinical trials. The application is based on a positive opinion we received from the EMEA’s Scientific Advice Working Party, or SAWP; the EMEA agreed that switching the primary endpoint from superiority to noninferiority is feasible if the retrospective justification provided in the marketing application is adequate. The discussions with the SAWP focused on using the STELLAR 4 study as primary evidence of non-inferiority and the STELLAR 3 study as supportive of the MAA. The application will be formally reviewed for validation by the end of March. Upon validation, the marketing approval review process begins, which generally takes 15 to 18 months.

We are also developing paclitaxel poliglumex for women with pre-menopausal levels of estrogen who have advanced NSCLC with normal or poor performance status. The basis for this clinical study was in part related to a pooled analysis of STELLAR 3 and 4 phase III trials for treatment of first-line NSCLC patients who have PS2, which we believe demonstrates a statistically significant survival advantage among women receiving paclitaxel poliglumex when compared to women or men

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receiving standard chemotherapy. A survival advantage for women over men was also demonstrated in a first-line phase II clinical trial of paclitaxel poliglumex and carboplatin, known as the PGT202 trial, supporting the potential benefit observed in the STELLAR 3 and 4 trials. In December 2005, we initiated a phase III clinical trial, known as the PIONEER, or PGT305, study, for paclitaxel poliglumex as first-line monotherapy in PS2 women with NSCLC. In December 2006, we agreed with the recommendation of the Data Safety Monitoring Board to close the PIONEER lung cancer clinical trial due, in part, to the diminishing utility of the PIONEER trial given our plans to submit a new protocol to the FDA. In early 2007, we submitted two new protocols under a Special Protocol Assessment, or SPA, to the FDA. The new trials, known as PGT306 and PGT307, focus exclusively on NSCLC in women with pre-menopausal estrogen levels, the subset of patients where paclitaxel poliglumex demonstrated the greatest potential survival advantage in the STELLAR trials. We believe the lack of safe and effective treatment for women with advanced first-line NSCLC who have pre-menopausal estrogen levels represents an unmet medical need. We initiated the PGT307 trial in September 2007. Although the FDA has established the requirement that two adequate and well-controlled pivotal studies demonstrating a statistically significant improvement in overall survival will be required for approval of paclitaxel poliglumex in the NSCLC setting, we believe that compelling results from a single trial, PGT307, along with supporting evidence from prior clinical trials, may enable us to submit a new drug application, or NDA, in the United States. In early 2008, we limited enrollment on the PGT307 study to U.S. sites only, until either approval of the MAA by the EMEA or until positive results from the GOG212 trial of paclitaxel poliglumex for first-line maintenance therapy in ovarian cancer are reported.

We are also developing paclitaxel poliglumex as potential maintenance therapy for women with advanced stage ovarian cancer who achieve a complete remission following first-line therapy with paclitaxel and carboplatin. This study is under the control of the Gynecologic Oncology Group and is expected to enroll 1,100 patients by 2010. A potential interim analysis, based on the number of events in the database, is planned for 2009, and if successful could lead to an NDA filing in 2010.

We are developing pixantrone, a novel anthracycline derivative, for the treatment of NHL. An interim analysis of our ongoing phase III study of pixantrone, known as the EXTEND or PIX301 study, was performed by the independent Data Monitoring Committee in the third quarter of 2006. Based on their review, the study continued. In September 2007, we announced that we reduced the enrollment target and decided to conduct a full analysis of the EXTEND trial, instead of an interim analysis as previously planned. In March 2008, we completed enrollment of approximately 140 patients in the EXTEND trial, 97 of which are currently evaluable according to Histological Intent to Treat, or HITT, criteria. An analysis of the data is expected in the second half of 2008 and, if final study results are adequate, we could submit an NDA with the FDA in early 2009 with potential approval in the second half of 2009. The FDA agreed that randomized safety data from the RAPID study (CHOP-R vs. CPOP-R) could be used to support the EXTEND results in an NDA submission for pixantrone. The RAPID, or PIX203, study is a phase II study in which pixantrone is substituted for doxorubicin in the CHOP-R regimen compared to the standard CHOP-R regimen in patients with previously untreated diffuse large B-cell lymphoma. An interim analysis of the RAPID study was reported in July 2007. The interim analysis of the study showed that to date a majority of patients on both arms of the study achieved a major objective anti-tumor response (complete response or partial response). Patients on the pixantrone arm of the study had clinically significant reductions in the incidence of severe heart damage, infections, and thrombocytopenia (a reduction in platelets in the blood) as well as significant reduction in febrile neutropenia. Three deaths occurred in the pixantrone arm versus none in the control arm. Based on subsequent follow-up, we believe this discrepancy is probably due to the early nature of the data. In early 2008, we closed enrollment on the RAPID trial because we had adequate sample size to demonstrate differences in cardiac events and other clinically relevant side effects between pixantrone and doxorubicin.

We also launched a phase III trial of pixantrone in indolent NHL, the PIX303 trial, in September 2007, which was designed to evaluate the combination of fludarabine, pixantrone and rituximab versus fludarabine and rituximab in patients who have received at least one prior treatment for relapsed or refractory indolent NHL. We closed the PIX303 trial in early 2008 based on, among other considerations, our plans to refocus the Company’s resources on obtaining pixantrone approval based on the EXTEND phase III trial before making additional substantive investments in alternative indications for pixantrone as well as the changing competitive landscape in second line follicular NHL. In May 2007, we received fast track designation from the FDA for pixantrone for the treatment of relapsed or refractory indolent NHL.

We are developing brostallicin, which is a small molecule, anti-cancer drug with a novel, unique mechanism of action and composition of matter patent coverage, through our wholly owned subsidiary, SM. Data in more than 200 patients treated with brostallicin in phase I/II clinical trials reveal evidence of activity in patients with refractory cancer and patient/physician-friendly dosage and administration. A phase II study of brostallicin in relapsed/refractory soft tissue sarcoma met its pre-defined activity and safety hurdles and resulted in a first-line phase II study that is currently being conducted by the European Organization for Research and Treatment of Cancer, or EORTC. Additionally, we initiated a phase II myxoid liposarcoma trial in 2007. Brostallicin also has demonstrated synery with new targeted agents as well as established treatments in preclinical trials; consequently, we have begun a multi-arm combination study with brostallicin and other agents, including Avastin. This study is being conducted in conjunction with U.S. Oncology at multiple sites in the United States with the first combinations expected to be completed in 2008.

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We are developing Zevalin for additional indications. Zevalin is a form of cancer therapy called radioimmunotherapy and is indicated for the treatment of patients with relapsed or refractory low-grade, follicular, or B-cell NHL, including patients with Rituximab-refractory follicular NHL. It was approved by the FDA in February 2002 as the first radioimmunotherapeutic agent for the treatment of NHL. At the American Society of Hematology meeting in December 2007, Bayer Schering, which holds the rights to Zevalin outside of the United States, published the results of their Phase III first-line indolent trial of Zevalin, known as the FIT trial. In March 2008, Bayer Schering received a positive opinion from the European Committee for Medicinal Products for Human Use, or CHMP, recommending Zevalin as consolidation therapy after remission induction in previously untreated patients with follicular lymphoma in Europe. Upon a favorable review by the European Commission, Bayer Schering could receive marketing authorization for this indication of Zevalin later this year. While we do not currently have any rights to use or access the data from the FIT trial, we intend to negotiate with Bayer Schering for access to those results. If we are successful in obtaining access to the FIT trial results and the data is suitable for FDA filing, we plan to submit a supplemental biologics license application, or sBLA, for Zevalin consolidation of first remission in advanced stage follicular lymphoma in the second half of 2008. We also intend to file an sBLA to remove the requirement for a biodistribution scan from the Zevalin label in 2008.

We are currently focusing our efforts on Zevalin, paclitaxel poliglumex, pixantrone, and brostallicin, and have no immediate plans to conduct any further clinical studies on CT-2106, polyglutamate camptothecin, or any other early-stage drug candidates.

“CTI” and “XYOTAX” are our proprietary marks, and we also own the U.S. rights to the mark “Zevalin”. All other product names, trademarks and trade names referred to in this Form 10-K are the property of their respective owners.

As of December 31, 2007, we had incurred aggregate net losses of approximately $1.1 billion since inception. We expect to continue to incur additional operating losses for at least the next couple of years.

Recent Developments

Debt Restructuring

We have a substantial amount of debt outstanding, and our annual interest expense with respect to our debt is significant. We recently completed partial restructurings of our 2008 convertible notes in December 2007 and February 2008, which retired a portion of such debt, extended the maturity date on a portion of such debt to 2011 and involved the issuance of additional shares of common stock to holders of the exchanged notes. However, approximately $10.7 million of such 2008 convertible notes remain outstanding and are due on June 15, 2008. We may consider additional alternatives to satisfy our obligations on the remaining outstanding 2008 convertible notes.

On January 30, 2008, we announced a plan to refocus our resources on late-stage and marketed products, which involve increasing sales of Zevalin in the United States and preparing the marketing applications for XYOTAX and pixantrone described above, while advancing the clinical development of brostallicin. This plan is intended to reduce operating expenses throughout the company by approximately 35% and reduce the company’s projected net cash operating expenses to a forecasted $77 million in 2008. As part of these refocusing efforts, approximately 30 of our U.S. employees were terminated.

As of December 31, 2007 we had cash and cash equivalents, securities available-for- sale and interest receivable of approximately $18.4 million, and total current liabilities of $53.5 million. We currently forecast net cash operating expenses of approximately $77 million in 2008. As a result, we will need to continue to raise additional capital to fund our operations in 2008 and beyond. See “Risk Factors.”

Recent Financings

In December 2007, we sold 6,500 shares of our Series D 7% Convertible Preferred Stock and warrants to purchase 1,244,016 shares of our common stock to institutional investors for aggregate gross proceeds of $6.5 million. In addition, we also sold 3,469,999 shares of common stock and warrants to purchase an additional 3,469,999 shares of common stock at $2.02 per share in a registered offering in December 2007 to institutional investors for aggregate gross proceeds of approximately $7.0 million.

In January 2008, we sold 800,000 shares of our common stock to Société Générale under the Step-Up Equity Financing Agreement we have in place with Société Générale. The 800,000 shares of common stock were sold at a price of € 1.07, or approximately $1.59, per share, which raised $1,272,000 (€ 856,000) in aggregate gross proceeds.

        On March 3, 2008 we issued approximately $51.7 million of our 9% convertible senior notes due 2012 plus warrants to purchase 7,326,950 shares of our common stock at an exercise price of $1.41 per share. The notes will bear interest at an annual rate of 9% and be convertible into our common stock at an initial rate of approximately 709.22 shares per $1,000 principal amount of the notes, which is equivalent to an initial conversion price of approximately $1.41. Upon conversion of the notes, we will be required to pay a make-whole amount to the holders of the converted notes equal to $270 per $1,000 principal amount of the converted notes less any interest paid on such notes prior to the conversion date, or make-whole payment. An amount adequate to pay the make-whole payments on all outstanding notes will be held in escrow for a period of one year. As of March 19, 2008, $28.8 million of these notes had been converted.

In connection with this debt issuance, certain existing holders of our series A, B, C, and D convertible preferred stock converted their shares of preferred stock into common stock. These conversions included 6,300, 10,162, 2,000 and 3,000 shares of series A, B, C and D convertible preferred stock, respectively. To induce these conversions, we paid an aggregate cash payment of approximately $16.2 million.

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Recent Legal Proceedings

Based on language (the “Disputed Language”) contained in the Articles of Amendment to the Company’s Articles of Incorporation (the “Amendments”) filed in connection with the issuance of the Company’s Series A, Series B and Series C Convertible Preferred Stock (the “Preferred Stock”), certain holders thereof (the “Shareholders”) asserted a right to consent (or not) to the transactions contemplated by the Exchange Agreements entered into by the Company and certain holders of its then existing convertible debt on December 12, 2007 (the “Exchange”). The Company is of the view that inclusion of the Disputed Language in the Amendments constitutes a scrivener’s error without legal force or effect, and filed Articles of Correction with the Secretary of State of Washington in accordance with Section 23B.01.240 of the Revised Code of Washington. On January 2, 2008, Tang Capital Partners LP (“Tang”) filed a civil action in the United States District Court for the Southern District of New York in which Tang alleged that the Company breached a Securities Purchase Agreement, executed on or about April 16, 2007 in connection with the issuance of Series B Preferred Stock. Tang alleges that the Company’s filing of Articles of Correction to the Articles of Amendment to the Amended and Restated Articles of Incorporation on or around December 11, 2007 materially and adversely altered the powers, preferences or rights conferred through its Securities Purchase Agreement, thereby constituting a Triggering Event, and as a result, Tang is entitled to redemption of its Preferred Stock in consideration for 130% of its Stated Value, plus other available relief, if any. One other holder of Preferred Stock, Enable Capital Management LLC, asserted similar claims in correspondence with the Company in December 2007 and in January 2008 subsequently filed a lawsuit with similar claims to the Tang action. At this time, we are not able to make a determination whether the likelihood of an unfavorable outcome is probable or remote.

Other Information

We were incorporated in Washington in 1991. Our principal executive offices are located at 501 Elliott Avenue West, Suite 400, Seattle, Washington 98119. Our telephone number is (206) 282-7100. Our website can be found at www.CellTherapeutics.com. Information contained in, or accessible through, our website does not constitute a part of this prospectus supplement.

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The Offering

The following is a brief summary of some of the terms of the notes and shares of common stock offered for resale in this prospectus. For a more complete description of the terms of the notes, see the “Description of Notes” section in this prospectus. For a more complete description of the terms of the common stock, see the “Description of Capital Stock” section in this prospectus.

Securities Offered	$23,250,000 aggregate principle amount, 1,170,213 shares of common stock, and 7,749,992 shares of common stock issuable upon conversion of the notes.
Issuer	Cell Therapeutics, Inc.
Maturity	The notes mature December 15, 2011.
Offering Price	100% of the principal amount.
Interest	Interest is payable on the notes at a rate of 5.75% per annum, payable in cash, common stock or some combination of common stock having a fair market value equal to the interest payment due, semi-annually on June 15 and December 15 of each year, beginning on June 15, 2008. For purposes of this provision, the fair market value of our common stock shall be equal to 95% of its volume-weighted average price for the five consecutive trading days ending on the trading day immediately preceding the interest payment date.
Conversion	Holders have the option to convert the notes into shares of our common stock at a conversion rate of 333.333 shares of common stock per $1,000 principal amount of the notes, which is equivalent to a conversion price of $3.00 per share. The conversion rate is subject to adjustment as described more fully in “Description of Notes—Conversion Rights.” Holders may convert the notes at any time before the close of business on the maturity date, unless we have previously redeemed or repurchased the notes; provided, however, that if a note is subject to redemption, holders will be entitled to convert the note at any time before the close of business on the date immediately preceding the date fixed for redemption. See “Description of Notes—Conversion Rights.”
Optional Redemption	Prior to December 15, 2009, we will not have the right to redeem any notes at our option. On or after December 15, 2009, we may redeem some or all of the notes for cash at any time at a redemption price equal to 100% of the aggregate principal amount of the outstanding notes at the time of such redemption plus a Make-Whole Payment and accrued and unpaid interest to, but not including, the redemption rate. See “Description of Notes—Optional Redemption.”
Automatic Conversion	Subject to certain conditions, the notes will automatically convert if, at any time after December 15, 2009 and prior to maturity, the closing price per share of our common stock has exceeded 140% of the conversion price then in effect for at least 20 trading days within any 30 consecutive trading day period. See “Description of Notes—Automatic Conversion.”
Repurchase at Option of Holders Upon Change in Control	Upon certain changes in control (as defined in the indenture), holders will have the right, subject to certain conditions and restrictions, to require us to repurchase their notes, in whole or in part, at a repurchase price equal to 100% of the aggregate principal amount of such holders’ outstanding notes at the time of such repurchase, plus a Make-Whole Payment and accrued and unpaid interest to, but not including, the repurchase date. We are required to pay 100% of the aggregate principal amount of the notes in cash to holders upon such a repurchase. See “Description of Notes—Repurchase Option of Holders Upon Change in Control.”

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Make-Whole Provision	Upon automatic conversion of the notes, or upon exercise of the right to option redemption or repurchase upon change in control (as defined in the indenture), we will pay the holder an amount equal to $115 per $1,000 principal amount of the notes so converted, repurchased or redeemed less the amount of any interest paid on such notes prior to the conversion, repurchase or redemption date. This payment may be made in cash, common stock or some combination of cash and common stock. For purposes of this provision, the fair market value of our common stock shall be equal to 95% of its volume-weighted average price for the five consecutive trading days ending on the trading day immediately preceding the conversion, repurchase or redemption date. No make-whole amount shall be payable upon any conversion, repurchase or redemption of the notes other than in connection with the an automatic conversion of the notes, repurchase of the notes in connection with a change in control (as defined in the indenture) or an optional redemption by the Company. See “Description of Notes—Make-Whole Provision.”
Ranking	The notes rank pari passu in right of payment with all of our existing and future senior indebtedness, including our 6.75% Convertible Senior Notes due 2010, 7.5% Convertible Senior Notes due 2011 and 9% Convertible Senior Notes due 2012 and rank senior in right of payment to our currently outstanding 5.75% Convertible Senior Subordinated notes due June 2008, 5.75% Convertible Subordinated Notes due June 2008 and 4% Convertible Senior Subordinated Notes due 2010. The notes are also effectively senior in right of payment to liabilities of our subsidiaries. See “Description of Notes—Ranking.”
Use of Proceeds	We will not receive any proceeds from the sale by any selling securityholder of the notes or the shares offered by this prospectus.
Covenants	We have agreed not to incur or suffer to exist, and to not permit our subsidiaries to incur or suffer to exist (i) any indebtedness that is structurally senior or senior by its terms to these notes, or (ii) secured indebtedness, in an aggregate principal amount for both clauses (i) and (ii) exceeding $10,000,000 unless, in the case of clause (ii) only, these notes are equally and ratably secured with such secured indebtedness, except that we may incur liens or encumbrances in connection with biopharmaceutical licensing and/or partnering arrangements without any such limitations.

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Events of Default

The following will be events of default under the indenture for the notes: we fail to pay the principal of or any premium on the notes when due; we fail to pay any interest on the notes when due and that default continues for 30 days; we fail to give the notice that we are required to give if there is a change in control (as defined in the indenture); we fail to perform any other covenant in the indenture and that failure continues for 30 days after written notice to us by the trustee or the holders of at least $1,000,000 in aggregate principal amount of outstanding notes; we fail to pay when due the principal of any indebtedness for money borrowed by us or any of our subsidiaries in excess of $10 million if the indebtedness is not discharged and such failure continues for 30 days or more, or if such indebtedness has been accelerated and such acceleration is not annulled, within 30 days after written notice to us by the trustee or the holders of at least $1,000,000 in aggregate principal amount of the outstanding notes; we fail to pay when due any amount due to preferred stock holders of the company or any subsidiary and that failure continues for 30 days, or if the liquidation preference of such preferred stock has been accelerated and such acceleration is not annulled, within 30 days after written notice to us by the trustee or the holders of at least $1,000,000 in aggregate principal amount of the notes; the Company or a subsidiary redeems, purchases or otherwise acquires directly or indirectly any preferred stock in exchange for cash, cash equivalents or indebtedness with a maturity prior to that of these notes, except after payment of outstanding principal and any accrued interest on these notes; and certain events of bankruptcy, insolvency or reorganization with respect to Cell Therapeutics, Inc. and its significant subsidiaries specified in the indenture. See “Description of Notes—Events of Default.”

Nasdaq Global Market Symbol for Our Common Stock

CTIC

Financial Ratios

Our ratio of earnings to fixed charges for each of the periods indicated is as follows:

	Year Ended December 31,
	2003	2004	2005	2006	2007
Ratio of earnings to fixed charges(1)	—	—	—	—	—

(1) For the purposes of computing ratio of earnings to fixed charges, earnings consist of income (loss) before provision for income taxes plus fixed charges. Fixed charges consist of interest charges and that portion of rental payments under operating leases we believe to be representative of interest. Earnings for the years ended December 31, 2003, 2004, 2005, 2006 and 2007, were insufficient to cover fixed charges by $130,031, $252,298, $102,505, $135,819 and $148,305 (in thousands) respectively. For this reason, no ratios are provided for these periods.

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RISK FACTORS

You should carefully consider the risks described below and other information in this prospectus supplement and in the documents incorporated by reference into this prospectus supplement before deciding to invest in our securities. Additional risks and uncertainties that we do not presently know or that we currently deem immaterial may also impair our business, financial condition, operating results and prospects. If any of the following risks actually occur, they could materially adversely affect our business, financial condition, operating results or prospects. In that case, the trading price of our securities could decline.

Factors Affecting Our Operating Results and Financial Condition

We expect to continue to incur net losses, and we might never achieve profitability.

We were incorporated in 1991 and have incurred a net operating loss every year. As of December 31, 2007, we had an accumulated deficit of approximately $1.1 billion. We are pursuing regulatory approval for paclitaxel poliglumex, pixantrone, brostallicin and plan to seek regulatory approval for the expansion of approved uses of Zevalin. We will need to conduct research, development, testing and regulatory compliance activities and undertake manufacturing and drug supply activities, expenses which, together with projected general and administrative expenses, will result in operating losses for the foreseeable future. We may never become profitable, even if we are able to commercialize products currently in development or otherwise.

Our debt and operating expenses exceed our net revenues.

We have a substantial amount of debt outstanding, and our annual interest expense with respect to our debt is significant. We have a single drug we are marketing, Zevalin, and the net proceeds of sales of this drug are not sufficient to pay our debt and operating expenses on a current basis. We do not currently project that net revenues from sales of any of our products will be sufficient to cover our existing debt and operating expenses within the next twelve months. Unless we raise substantial additional capital, we will not be able to repay this debt or the interest, liquidated damages or other payments that may become due with respect to our debt. Approximately $10.7 million of this debt is due in June 2008. Prior to this debt becoming due, we may engage in one or more restructuring transactions which could involve, among other things, an effective increase in interest rates, alteration of terms or exchanges involving the issuance of additional shares of common stock or other arrangements which may dilute or be adverse to the value of our common stock and preferred stock.

We need to raise additional funds immediately and expect that we will need to continue to raise funds in the future, and funds may not be available on acceptable terms, or at all.

In 2007, we were able to raise capital through the sale of preferred stock and common stock, and raised a total of $91.0 million in gross proceeds, with an additional $1.3 million in gross proceeds raised from an equity offering under our Step-Up Equity Financing Agreement with Société Générale in January 2008 and approximately $35.5 million in proceeds from a convertible debt offering, net of inducement payments for conversions of convertible preferred stock, in March 2008. In addition, approximately $13.9 million of this amount is restricted and is being held in escrow to fund potential make-whole payments due upon conversions of this debt. However, we have substantial operating expenses associated with the development of our product candidates and as of December 31, 2007 we had cash and cash equivalents, securities available-for-sale and interest receivable of approximately $18.4 million, and total current liabilities of approximately $53.5 million. We also have a substantial amount of debt outstanding, including an aggregate of approximately $152.5 million in convertible notes as of March 19, 2008, of which $10.7 million is due in June 2008. Furthermore, as a result of our preferred stock financings in 2007, we may be obligated to redeem such preferred stock starting in February 2009. We expect that our existing cash and cash equivalents, securities available-for-sale and interest receivable, including proceeds received from our offerings through March 15, 2008, will not provide sufficient working capital to fund our presently anticipated operations for the next 12 months and repay our notes due in June 2008, and we will therefore need to raise additional capital.

We have a €60 million (approximately $88 million as of December 31, 2007) Step-Up Equity Financing Agreement with Société Générale which we may be able to utilize to provide additional equity funding. As of March 19, 2008 we had approximately €59.1 million available under this financing agreement. Additionally, we may raise such capital through public or private equity financings, partnerships, joint ventures, dispositions of assets, debt financings or restructurings, bank borrowings or other sources. However, additional funding, including any obtained under the Financing Agreement, may not be available on favorable terms or at all. If adequate funds are not otherwise available, we will further curtail operations significantly, including the delay, modification or cancellation of operations and plans related to paclitaxel poliglumex, pixantrone, brostallicin, expanded uses of Zevalin and other products we may be developing. To obtain additional funding, we may need to enter into arrangements that require us to relinquish rights to certain technologies, drug candidates, products and/or potential markets. In addition, some financing alternatives may require us to meet additional regulatory requirements in Italy and the U.S., which may increase our costs and adversely affect our ability to obtain financing. To the extent that additional capital is raised through the sale of equity, or securities convertible into equity, shareholders may experience dilution of their proportionate ownership of us.

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We have received a going concern opinion on our consolidated financial statements

Due to our need to raise additional financing to fund our operations and satisfy obligations as they become due, our independent registered public accounting firm has included an explanatory paragraph in their report on our December 31, 2007 consolidated financial statements regarding their substantial doubt as to our ability to continue as a going concern. This may have a negative impact on the trading price of our common stock and we may have a more difficult time obtaining necessary financing.

We may be unable to obtain a quorum for meetings of our shareholders and therefore be unable to take certain corporate actions.

Our bylaws require that a quorum, consisting of a majority of the outstanding shares of voting stock, be represented in person or by proxy in order to transact business at a meeting of our shareholders. A substantial number of our common shares are held by Italian institutions and under Italian laws and regulations, it is difficult to communicate with the beneficial holders of those shares to obtain votes. In 2006, we scheduled two annual meetings of shareholders but were unable to obtain quorum at either meeting. Following that failure to obtain quorum, we contacted certain depository banks in Italy where significant numbers of shares of our common stock were held and asked them to cooperate by making a book entry transfer of their share positions at Monte Titoli to their U.S. correspondent bank, who will then transfer the shares to an account of the Italian bank at a U.S. broker-dealer that is an affiliate of that bank. Certain of the banks contacted agreed to make the share transfer pursuant to these arrangements as of the record date of the meeting, subject to the relevant beneficial owner taking no action to direct the voting of such shares. Under Rule 452 of the New York Stock Exchange, the U.S. broker-dealer may vote shares absent direction from the beneficial owner on certain matters, such as the uncontested election of directors, an amendment to the Company’s articles of incorporation to increase authorized shares that are to be used for general corporate purposes, and the ratification of our auditors, in the event that the broker receives no voting instruction from the beneficial owner. As a result of this custody transfer, we were able to hold a special meeting of the shareholders in April 2007, an annual meeting of the shareholders in September 2007 and another special meeting of the shareholders in January 2008. However, obtaining a quorum at future meetings depends in part upon the willingness of the Italian depository banks to continue participating in the custody transfer arrangements, and we cannot be assured that those banks that have participated in the past will continue to participate in custody transfer arrangements in the future. We are continuing to explore other alternatives to achieve quorum for our meetings, however, we cannot be certain that we will find an alternate method if we are unable to continue to use the custody transfer arrangements. As a result, we may be unable to obtain quorum at future annual or special meetings of shareholders. If we are unable to obtain a quorum at our shareholder meetings and thus fail to get shareholder approval of corporate actions, such failure could have a materially adverse effect on the Company. In addition, brokers may only vote on those matters for which broker discretionary voting is allowed under Rule 452, and we may not be able to obtain the required number of votes to approve certain proposals that require a majority of all outstanding shares to approve the proposal due to our reliance on broker discretionary voting. Therefore it is possible that even if we are able to obtain a quorum for our meetings of the shareholders we still may not receive enough votes to approve proxy proposals presented at such meeting and, depending on the proposal in question, such failure could have a materially adverse effect on the Company.

We could fail in financing efforts if we fail to receive shareholder approval when needed.

We are required under the Nasdaq Marketplace Rules to obtain shareholder approval for any issuance of additional equity securities that would comprise more than 20% of our total shares of common stock outstanding before the issuance of the securities at a discount to the greater of book or market value in an offering that is not deemed to be a “public offering” by Nasdaq. Funding of our operations in the future may require issuance of additional equity securities that would comprise more than 20% of our total shares of common stock outstanding, but we might not be successful in obtaining the required shareholder approval for such an issuance, particularly in light of the difficulties we have experienced in obtaining a quorum and holding shareholder meetings as outlined above.

We are required to comply with the regulatory structure of Italy because our stock is traded on the MTA, which could result in administrative challenges.

Our stock is traded on the MTA stock market in Milan, Italy and we are required to also comply with the rules and regulations of the Commissione Nazionale per le Società e la Borsa, or CONSOB, which is the public authority responsible for regulating the Italian securities market and the Borsa Italiana, which ensures the development of the managed market in Italy. Collectively these agencies regulate companies listed on Italy’s public markets. Conducting our operations in a manner that

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complies with all applicable laws and rules requires us to devote additional time and resources to regulatory compliance matters. For example, the process of seeking to understand and comply with the laws of each country, including tax, labor and regulatory laws, might require us to incur the expense of engaging additional outside counsel, accountants and other professional advisors and might result in delayed business initiatives as we seek to ensure that each new initiative will comply with all applicable regulatory regimes. Compliance with Italian regulatory requirements may delay additional issuances of our common stock; we are currently taking steps to attempt to conform to the requirements of the Italian stock exchange and CONSOB to allow such additional issuances.

In addition, under Italian law, we must publish a listing prospectus that has been approved by CONSOB prior to issuing common stock in any twelve-month period that exceeds 10% of the number of shares of common stock outstanding at the beginning of that period. We have attempted to publish a listing prospectus in Italy to cover our general offerings for the past year. We filed our initial listing prospectus with CONSOB in April 2007 and worked with CONSOB to meet their requirements to publish that listing prospectus for the remainder of 2007. We were finally able to publish a listing prospectus in January 2008, however, that listing prospectus was limited to shares to be issued to Société Générale under the Step-Up Equity Financing Agreement we entered into with Société Générale in 2006. We continue to pursue the possibility of publishing a listing prospectus to cover other financing efforts under Italian law, however, at the present time we have not been successful in getting approval from the Italian regulators for such a listing prospectus. As a result, we are required to raise money using alternative forms of securities; for example, we use convertible preferred stock and convertible debt in lieu of common stock as convertible preferred stock and convertible debt are not subject to the 10% limitation imposed by Italian law.

In 2006, we identified material weaknesses in our internal control over financial reporting and we received an adverse opinion on internal control over financial reporting from our independent registered public accounting firm in connection with their annual internal control attestation process for fiscal year 2006.

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of the company’s annual or interim financial statements will not be prevented or detected on a timely basis. We identified that as of December 31, 2006 we had the following material weaknesses relative to the effectiveness of our internal control over financial reporting:

• We did not maintain an effective review and approval process in our European subsidiary, or CTI (Europe), to ensure the accuracy of accounts payable and accrued expenses for certain activities shared by headquarters and CTI (Europe) in conformity with generally accepted accounting principles.

• We did not maintain effective internal controls related to the financial reporting process to detect errors that are not identified by the process level controls in CTI (Europe).

During 2007, to remedy the material weaknesses in our internal control over financial reporting, we implemented enhanced review and approval procedures that are designed to help ensure we accurately record accounts payable and accrued expense balances in CTI (Europe), and trained personnel in key finance positions in CTI (Europe) regarding the enhanced procedures and appropriate levels of oversight and review.

In November 2007, we merged CTI (Europe) with and into CTI in a roll-up merger under Washington law. As a result, all of our operations in Italy are now directly part of CTI and CTI (Europe) is now a branch of the Company.

The existence of a material weakness is an indication that there is a reasonable possibility that a material misstatement of our annual or interim financial statements will not be prevented or detected on a timely basis. If we fail to maintain an effective system of internal controls, we may not be able to report our financial results accurately, which may deprive management of important financial information needed to manage the Company effectively, may cause investors to lose confidence in our reported financial information and may have an adverse effect on the trading price of our common stock.

If we are not able to successfully identify and complete valuable acquisition opportunities, we may not achieve the anticipated growth we would otherwise achieve were such acquisitions accomplished.

We have in the past and may in the future seek to further expand our product portfolio through acquisitions of other complementary businesses or technologies or marketed products. For example, in July 2007, we acquired SM, a privately held oncology company, and gained worldwide rights to brostallicin, a DNA minor groove binding agent with proven anti-tumor activity which is currently in phase II clinical studies. Additionally, in December 2007, we acquired Zevalin from Biogen Idec, or Biogen, for development, marketing and sale in the United States. Mergers and acquisitions are inherently risky, and we cannot assure that we will be able to complete future acquisitions, or that our acquisitions will be successful. The successful execution of our acquisition strategy will depend, in part, on our ability to identify, negotiate, complete and integrate such

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acquisitions and, if necessary, obtain satisfactory debt or equity financing to fund those acquisitions. Failure to manage and successfully integrate acquired businesses could harm our business.

If we are not able to successfully integrate recent and future acquisitions, our management’s attention could be diverted, and efforts to integrate future acquisitions could consume significant resources.

The acquisitions of SM and of Zevalin or any other future acquisition that we may undertake, involve numerous risks related to the integration of the acquired asset or entity into the Company after the acquisition is completed. These risks include the following:

• difficulties in integrating the operations, technologies, and products of the acquired companies;

• difficulties in implementing internal controls over financial reporting;

• diversion of management’s attention from normal daily operations of the business;

• inability to maintain the key business relationships and the reputations of acquired businesses;

• entry into markets in which we have limited or no prior experience and in which competitors have stronger market positions;

• dependence on unfamiliar affiliates and partners;

• reduction in the development or commercialization of existing products due to increased focus on the development or commercialization of the acquired products;

• responsibility for the liabilities of acquired businesses;

• inability to maintain our internal standards, controls, procedures and policies at the acquired companies or businesses; and

• potential loss of key employees of the acquired companies.

In addition, if we finance or otherwise complete acquisitions by issuing equity or convertible debt securities, our existing shareholders may be diluted.

If we are unable to expand label usage of Zevalin, or maintain or obtain improved reimbursement rates, we may not recognize the full value of the asset and there may be adverse effects on our expected financial and operating results.

We intend to seek expansion of the approved uses, or labeled uses, of Zevalin in the United States. However, we may be unable to obtain approval for such label expansion in full or in part. If we are not able to obtain approval for expansion of the labeled uses for Zevalin, or if we are otherwise unable to fulfill our marketing, sales and distribution plans for Zevalin, we may not recognize the full anticipated value of Zevalin. If we do not expand the approved uses of Zevalin, we may have insufficient net revenues to finance our current levels of debt and operations unless we are able to market and sell other products. While we intend to negotiate with Bayer Schering for access to data from their first line indolent trial, or FIT trial, we currently have no rights to that data, and there is no assurance that Bayer Schering will agree to give us access to their data on reasonable terms or at all. In addition, even if we are able to use the data from Bayer Schering’s FIT trial, there can be no guarantee that such data will be adequate or suitable for submission to the FDA in support of a supplemental biologics license application for additional approved uses of Zevalin, or that the FDA will approve such supplemental biologics license application.

In 2007, the Centers for Medicare and Medicaid Services, or CMS, implemented new outpatient reimbursement rates to be put in place in 2008 for radiopharmaceuticals, including Zevalin. These new rates are below the acquisition costs of Zevalin. Although Congress passed legislation in late 2007 to delay the implementation of those new rates and stabilize reimbursement rates for the first six months of 2008 with the intention of giving drug manufacturers and CMS more time to reach an agreement that more adequately reflects hospitals’ costs associated with the therapy, there can be no guarantee that CMS will agree to a rate or methodology that provides an acceptable reimbursement on radiopharmaceuticals such as Zevalin. In the event that CMS does not agree to a reimbursement rate that is adequate to cover the acquisition costs of Zevalin, we may face immediate and significant difficulty in getting care providers to use Zevalin, which would have an adverse impact on our expected financial and operating results.

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We may face difficulties in achieving broader market acceptance of Zevalin if we do not invest significantly in our sales and marketing infrastructure.

We currently market Zevalin using a direct sales force that we recently hired in connection with our acquisition of Zevalin from Biogen. U.S. sales of Zevalin by its prior owner either declined or remained flat over the past several years and we expect such sales to remain flat in 2008. We believe that our sales and marketing strategy, in conjunction with our efforts to obtain approval by the FDA for expanded uses of Zevalin, will increase sales of and revenue from Zevalin over the next few years. Our sales and marketing strategy intends to take advantage of the recent lowering of barriers to adoption, including greater economic incentives and practice efficiencies for Zevalin compared to rituximab, the recent adoption of positron emission tomography in community oncology practices, which facilitates use of Zevalin, and implementation of a Zevalin community access program, which targets facilitation of on-site ordering, receipt, and administration of Zevalin by the 100 largest community oncology group practices. However, implementation of the sales and marketing strategy will require an investment of resources and may not increase Zevalin revenues according to our forecasts. In addition, creation and expansion of an effective sales force may take time, and competition for sales and marketing personnel in our industry is intense. Therefore, we will need to effectively manage and expand our sales force, hire individuals with additional technical expertise, expand our distribution capacity or otherwise grow our sales and marketing infrastructure in order to achieve broader market acceptance and additional sales revenue from Zevalin. In addition to the factors just listed, if we do not effectively manage our sales force, our financial condition and operating results may suffer.

We may not realize any royalties, milestone payments or other benefits under the License and Co-Development agreement entered into with Novartis Pharmaceutical Company Ltd.

We have entered into a License and Co-Development agreement related to paclitaxel poliglumex and pixantrone with Novartis International Pharmaceutical Ltd., or Novartis, pursuant to which Novartis received an exclusive worldwide license for the development and commercialization of paclitaxel poliglumex and an option to enter into an exclusive worldwide license to develop and commercialize pixantrone. We will not receive any royalty or milestone payments under this agreement unless Novartis elects to participate in the development and commercialization of paclitaxel poliglumex or if Novartis exercises its option related to pixantrone and we are able to reach a definitive agreement. Novartis is under no obligation to make such election or exercise such right and may never do so. In addition, even if Novartis exercises such rights, any royalties and milestone payments we may be eligible to receive from Novartis are subject to the receipt of the necessary regulatory approvals and the attainment of certain sales levels. We may never receive the necessary regulatory approvals and our products may not reach the necessary sales levels.

We may be delayed, limited or precluded from obtaining regulatory approval of paclitaxel poliglumex given that our three STELLAR phase III clinical trials for the treatment of non-small cell lung cancer did not meet their primary endpoints.

There are no guarantees that we will obtain regulatory approval to manufacture, market, or expand the marketing of any of our drug candidates. Obtaining regulatory approval to market drugs to treat cancer is expensive, difficult, and risky. Preclinical and clinical data can be interpreted in different ways, which could delay, limit or preclude regulatory approval. Negative or inconclusive results or adverse medical events during a clinical trial could delay, limit or prevent regulatory approval.

Our future financial success depends in large part on obtaining regulatory approval of paclitaxel poliglumex. In March 2005, we announced the results of STELLAR 3, and in May 2005, we announced the results of STELLAR 2 and 4, our phase III clinical trials of paclitaxel poliglumex in non-small cell lung cancer. All three trials failed to achieve their primary endpoints of superior overall survival compared to current marketed agents for treating NSCLC.

In December 2006, we closed the PIONEER clinical trial and in 2007, we initiated a new study in the United States, PGT307, which focuses on the primary efficacy endpoint of survival in women with NSCLC and pre-menopausal estrogen levels. We have decided not to initiate an additional study, the PGT306 trial, for which we have submitted a special protocol assessment, or SPA, to conserve limited financial resources. We also feel that compelling evidence from one trial, the PGT307 trial, along with supporting evidence from earlier clinical trials, may be adequate to submit an NDA for paclitaxel poliglumex even though the FDA has established a requirement that two adequate and well-controlled pivotal studies demonstrating a statistically significant improvement in overall survival will be required for approval of paclitaxel poliglumex in the NSCLC setting. We may not receive compelling evidence or any positive results from the PGT307 trial, which would preclude our planned submission of an NDA to the FDA, and would preclude us from marketing paclitaxel poliglumex in the United States.

Based on discussions with the EMEA Scientific Advice Working Party, we submitted an MAA in Europe on March 4, 2008 based on results of the STELLAR trials, however a successful regulatory outcome from the EMEA is not assured as the EMEA’s final opinion cannot be predicted until they have had the opportunity to complete a thorough review of the clinical data that will be presented in the MAA.

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We are subject to extensive government regulation.

We are subject to rigorous and extensive regulation by the FDA in the United States and by comparable agencies in other states and countries. Failure to comply with regulatory requirements could result in various adverse consequences, including possible delay in approval or refusal to approve a product, withdrawal of approved products from the market, product seizures, injunctions, regulatory restrictions on our business and sales activities, monetary penalties, or criminal prosecution.

Our products may not be marketed in the United States until they have been approved by the FDA and may not be marketed in other countries until they have received approval from the appropriate agencies. With the exception of Zevalin, none of our current products have received approval. Obtaining regulatory approval requires substantial time, effort and financial resources, and we may not be able to obtain approval of any of our products on a timely basis, or at all. If our products are not approved quickly enough to provide net revenues to defray our debt and operating expenses, our business and financial condition will be adversely affected.

Our marketed products, such as Zevalin, are and will be subject to extensive regulations regarding their promotion and commercialization. For instance, we are subject to numerous regulations and statutes regulating the manner of selling and obtaining reimbursement for our products that receive marketing approval. For example, federal statutes generally prohibit providing certain discounts and payments to physicians to encourage them to prescribe our product. Violations of such regulations or statutes may result in treble damages, criminal or civil penalties, fines or exclusion of CTI or its employees from participation in federal and state health care programs. Although we have policies prohibiting violations of relevant regulations and statutes, unauthorized actions of our employees or consultants, or unfavorable interpretations of such regulations or statutes may result in third parties or regulatory agencies bringing legal proceedings or enforcement actions against us. Because our sales force is relatively new, we may have a greater risk of such violations from lack of adequate training or experience. The expense to retain and pay legal counsel and consultants to defend against any such proceedings would be substantial, and together with the diversion of management’s time and attention to assist in any such defense, may negatively affect our financial condition and results of operations.

In addition, both before and after approval, our contract manufacturers and our products are subject to numerous regulatory requirements covering, among other things, testing, manufacturing, quality control, labeling, advertising, promotion, distribution and export. Manufacturing processes must conform to current Good Manufacturing Practice, or cGMPs. The FDA and other regulatory authorities periodically inspect manufacturing facilities to assess compliance with cGMPs. Accordingly, manufacturers must continue to expend time, money and effort to maintain compliance. Failure to comply with FDA, EMEA or other applicable regulations may cause us to curtail or stop the manufacture of such products until we obtain regulatory compliance.

The marketing and promotion of pharmaceuticals is also heavily regulated, particularly with regard to prohibitions on the promotion of products for off-label uses. In April 2007, we paid a civil penalty of $10.5 million and entered into a settlement agreement with the United States Attorney’s Office, or USAO, for the Western District of Washington arising out of their investigation into certain of our prior marketing practices relating to TRISENOX, which was divested to Cephalon Inc. in July 2005. As part of that settlement agreement, and in connection with the acquisition of Zevalin, a commercially approved drug, we also entered into a corporate integrity agreement with the HHS-OIG that requires us to establish a compliance committee and compliance program and adopt a formal code of conduct. The USAO settlement does not address separate claims brought against the Company by the private party plaintiff in this matter, which generally relate to attorney’s fees and employment related claims. In 2007, the United States District Court dismissed the private party plaintiff’s employment claims as barred by applicable statutes of limitation, and the private party plaintiff has advised us that he intends to seek a court order awarding approximately $1 million in attorneys’ fees. We are not able to reasonably estimate the potential cost of any award that may be made pursuant to this claim.

We rely on third parties for the manufacture and supply of Zevalin and for the manufacture and supply of radioactive isotopes used in the administration of Zevalin.

We currently rely on Biogen to manufacture and supply Zevalin to us through a long-term manufacturing agreement, and Biogen may, in turn, rely on other third-party manufacturers to fill its requirements for manufacturing Zevalin. If Biogen or any third party contract manufacturing organization, or CMO, or contract service provider, or CSP, upon which it relies does not produce or test and release Zevalin in sufficient quantities and on a timely and cost-effective basis, or if Biogen or any third party CMO or CSP does not obtain and maintain all required manufacturing approvals, our business could be harmed. In addition, we rely on MDS (Canada) for the manufacture and supply of Yttrium-90, a radioactive isotope used in the

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administration of Zevalin therapy. MDS (Canada) is currently our sole source of Yttrium-90, which must be manufactured and shipped in such a way as to ensure the appropriate potency of the isotope based on its radioactive half-life at the time of administration to the patient is valid. If MDS (Canada) were to have problems with the manufacture or supply of Yttrium-90, our business could be materially impacted, and we may not be able to find an additional supplier of the isotope on acceptable terms or at all. We also rely on Malinckrodt and GE for the manufacture and supply of Indium-111, a radioactive isotope used in the administration of Zevalin diagnostic for clinical purposes. Malinckrodt and GE are currently our two qualified sources of Indium-111, which must be manufactured and shipped in such a way as to ensure the appropriate potency of the isotope based on its radioactive half-life at the time of administration of the diagnostic dose to the patient. If both companies were to have problems with the manufacture or supply of Indium-111, our business could be materially impacted, and we may not be able to find an additional supplier of the isotope on acceptable terms or at all.

We face direct and intense competition from our competitors in the biotechnology and pharmaceutical industries, and we may not compete successfully against them.

Competition in the oncology market is intense and is accentuated by the rapid pace of technological development. We anticipate that we will face increased competition in the future as new companies enter the market. Our competitors in the United States and elsewhere are numerous and include, among others, major multinational pharmaceutical companies, specialized biotechnology companies and universities and other research institutions. Specifically:

• Zevalin currently competes with Bexxar^®, which is marketed by GlaxoSmithKline, and any rituximab-containing chemotherapy regimen. Rituximab is marketed in the U.S. by Genentech and Biogen Idec. In addition, other companies such as Cephalon, Eli Lilly, Genta, Genmab, Favrille, and Genitope are developing products which could compete with Zevalin.

• If we are successful in bringing paclitaxel poliglumex to market, we will face direct competition from oncology-focused multinational corporations. Paclitaxel poliglumex will compete with other taxanes. Many oncology-focused multinational corporations currently market or are developing taxanes, epothilones, and other cytotoxic agents, which inhibit cancer cells by a mechanism similar to taxanes, or similar products including, among others, Bristol-Myers Squibb Co. and others, which markets paclitaxel and generic forms of paclitaxel; Aventis, which markets docetaxel; Genentech and OSI Pharmaceuticals, which markets Tarceva™; Genentech, which markets Avastin™, Eli Lilly, which markets Alimta^®, and American Pharmaceutical Partners, which markets Abraxane™. In addition, other companies such as NeoPharm Inc. and Telik, Inc. are also developing products which could compete with paclitaxel poliglumex.

• Because pixantrone is intended to provide less toxic treatment to patients who have failed standard chemotherapy treatment, if pixantrone is brought to market, it is not expected to compete directly with many existing chemotherapies. However, pixantrone will face competition from currently marketed anthracyclines, such as mitoxantrone (Novantrone^®), and new anti-cancer drugs with reduced toxicity that may be developed and marketed.

• If we are successful in bringing brostallicin to market, we will face direct competition from other minor groove binding agents including Yondelis^®, which is currently developed by PharmaMar and has received Authorization of Commercialization from the European Commission for soft tissue sarcoma.

Many of our competitors, either alone or together with their collaborators and, in particular, the multinational pharmaceutical companies, have substantially greater financial resources and development and marketing teams than us. In addition, many of our competitors, either alone or together with their collaborators, have significantly greater experience than we do in developing, manufacturing and marketing products. As a result, these companies’ products might come to market sooner or might prove to be more effective, less expensive, have fewer side effects or be easier to administer than ours. In any such case, sales of our products or eventual products would likely suffer and we might never recoup the significant investments we are making to develop these product candidates.

Uncertainty regarding third-party reimbursement and healthcare cost containment initiatives may limit our returns.

The ongoing efforts of governmental and third-party payors to contain or reduce the cost of healthcare may affect our ability to commercialize our products successfully. Governmental and other third-party payors continue to attempt to contain healthcare costs by:

• challenging the prices charged for health care products and services,

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• limiting both coverage and the amount of reimbursement for new therapeutic products,

• denying or limiting coverage for products that are approved by the FDA but are considered experimental or investigational by third-party payors,

• refusing in some cases to provide coverage when an approved product is used for disease indications in a way that has not received FDA marketing approval, and

• denying coverage altogether.

The trend toward managed healthcare in the United States, the growth of organizations such as health maintenance organizations, and legislative proposals to reform healthcare and government insurance programs could significantly influence the purchase of healthcare services and products, resulting in lower prices and reducing demand for our products. In addition, in almost all European markets, pricing and choice of prescription pharmaceuticals are subject to governmental control. Therefore, the price of our products and their reimbursement in Europe will be determined by national regulatory authorities.

Even if we succeed in bringing any of our proposed products to the market, they may not be considered cost-effective and third-party reimbursement might not be available or sufficient. If adequate third-party coverage is not available, we may not be able to maintain price levels sufficient to realize an appropriate return on our investment in research and product development. As discussed above, CMS proposed new rates for 2008 for Zevalin that, if implemented, would result in reimbursement rates below our acquisition cost of Zevalin. In addition, legislation and regulations affecting the pricing of pharmaceuticals may change in ways adverse to us before or after any of our proposed products are approved for marketing.

Even if our drug candidates are successful in clinical trials, we may not be able to successfully commercialize them.

Since our inception in 1991, we have dedicated substantially all of our resources to the research and development of our technologies and related compounds. All of our compounds, with the exception of Zevalin, currently are in research or development, and have not received marketing approval.

Prior to commercialization, each product candidate requires significant research, development and preclinical testing and extensive clinical investigation before submission of any regulatory application for marketing approval. The development of anti-cancer drugs, including those we are currently developing, is unpredictable and subject to numerous risks. Potential products that appear to be promising at early stages of development may not reach the market for a number of reasons including that they may:

• be found ineffective or cause harmful side effects during preclinical testing or clinical trials,

• fail to receive necessary regulatory approvals,

• be difficult to manufacture on a scale necessary for commercialization,

• be uneconomical to produce,

• fail to achieve market acceptance, or

• be precluded from commercialization by proprietary rights of third parties.

The occurrence of any of these events could adversely affect the commercialization of our products. Products, if introduced, may not be successfully marketed and/or may not achieve customer acceptance. If we fail to commercialize products or if our future products do not achieve significant market acceptance, we will not likely generate significant revenues or become profitable.

The intellectual property and assets related to Zevalin are subject to a security agreement with Biogen; if we were to default on certain payments or reimbursement owed to Biogen or certain third parties, those assets would be subject to foreclosure by Biogen and we could lose our ability to continue development, sales and marketing activities with respect to Zevalin.

On December 21, 2007, in connection with our purchase of Zevalin, we entered into a Security Agreement with Biogen granting a first priority security interest to Biogen in all of our right, title and interest (a) in and to the assets related to Zevalin that we purchased from Biogen, together with any other assets or rights related to any of such assets or otherwise used in the development, manufacture or commercialization of Zevalin, and (b) under certain license, sublicense and supply agreements

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entered into in connection with our purchase of Zevalin. In the event we were to default on certain of our obligations under the Security Agreement, the Asset Purchase Agreement pursuant to which we continue to owe royalties and milestone payments to Biogen, or the related sublicense and service agreements, or in the event we were to make an application for, or consent to, the appointment of a receiver, trustee or liquidator of all or a substantial portion of our assets, transfer our assets as part of a general assignment or other arrangement for the benefit of creditors, become insolvent, file a voluntary or involuntary petition under the provisions of the United States Bankruptcy Code, or in the event of an attachment or execution upon, or seizure of, all or substantially all of our assets, Biogen may take any action with respect to the collateral under the Security Agreement that it deems necessary or advisable to accomplish the purposes of the Security Agreement. The Security Agreement will remain in effect until all obligations secured by that agreement have been satisfied. If Biogen were to foreclose on the collateral under this Security Agreement, it would have a material adverse impact on our business.

If any of our license agreements for intellectual property underlying Zevalin, paclitaxel poliglumex, pixantrone, brostallicin, or any other products are terminated, we may lose our rights to develop or market that product.

We have licensed intellectual property, including patent applications relating to intellectual property for pixantrone, brostallicin and Zevalin. We have also in-licensed the intellectual property for our drug delivery technology relating to paclitaxel poliglumex that uses polymers that are linked to drugs, known as polymer-drug conjugates. Some of our product development programs depend on our ability to maintain rights under these licenses. Each licensor has the power to terminate its agreement with us if we fail to meet our obligations under these licenses. We may not be able to meet our obligations under these licenses. If we default under any license agreements, we may lose our right to market and sell any products based on the licensed technology.

If we fail to adequately protect our intellectual property, our competitive position could be harmed.

Development and protection of our intellectual property are critical to our business. If we do not adequately protect our intellectual property, competitors may be able to practice our technologies. Our success depends in part on our ability to:

• obtain patent protection for our products or processes both in the United States and other countries,

• protect trade secrets, and

• prevent others from infringing on our proprietary rights.

When polymers are linked, or conjugated, to drugs, the results are referred to as polymer-drug conjugates. We are developing drug delivery technology that links chemotherapy to biodegradable polymers. For example, paclitaxel poliglumex is paclitaxel, the active ingredient in Taxol^®, one of the world’s best selling cancer drugs, linked to polyglutamate. We may not receive a patent for all of our polymer-drug conjugates and we may be challenged by the holder of a patent covering the underlying drug and/or methods for its use or manufacture.

The patent position of biopharmaceutical firms generally is highly uncertain and involves complex legal and factual questions. The U.S. Patent and Trademark Office has not established a consistent policy regarding the breadth of claims that it will allow in biotechnology patents. If it allows broad claims, the number and cost of patent interference proceedings in the United States and the risk of infringement litigation may increase. If it allows narrow claims, the risk of infringement may decrease, but the value of our rights under our patents, licenses and patent applications may also decrease. Patent applications in which we have rights may never issue as patents and the claims of any issued patents may not afford meaningful protection for our technologies or products. In addition, patents issued to us or our licensors may be challenged and subsequently narrowed, invalidated or circumvented. Litigation, interference proceedings or other governmental proceedings that we may become involved in with respect to our proprietary technologies or the proprietary technology of others could result in substantial cost to us. Patent litigation is widespread in the biotechnology industry, and any patent litigation could harm our business. Costly litigation might be necessary to protect a patent position or to determine the scope and validity of third-party proprietary rights, and we may not have the required resources to pursue any such litigation or to protect our patent rights. Any adverse outcome in litigation with respect to the infringement or validity of any patents owned by third parties could subject us to significant liabilities to third parties, require disputed rights to be licensed from third parties or require us to cease using a product or technology.

We also rely upon trade secrets, proprietary know-how and continuing technological innovation to remain competitive. Third parties may independently develop such know-how or otherwise obtain access to our technology. While we require our employees, consultants and corporate partners with access to proprietary information to enter into confidentiality agreements, these agreements may not be honored.

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Our products could infringe on the intellectual property rights of others, which may cause us to engage in costly litigation and, if unsuccessful, could cause us to pay substantial damages and prohibit us from selling our products.

We attempt to monitor patent filings but have not conducted an exhaustive search for patents that may be relevant to our products and product candidates in an effort to guide the design and development of our products to avoid infringement. We may not be able to successfully challenge the validity of these patents and could have to pay substantial damages, possibly including treble damages, for past infringement and attorneys’ fees if it is ultimately determined that our products infringe a third party’s patents. Further, we may be prohibited from selling our products before we obtain a license, which, if available at all, may require us to pay substantial royalties. Moreover, third parties may challenge the patents that have been issued or licensed to us. Even if infringement claims against us are without merit, or if we challenge the validity of issued patents, lawsuits take significant time, may be expensive and may divert management attention from other business concerns.

We may be unable to obtain the raw materials necessary to produce our paclitaxel poliglumex product candidate in sufficient quantity to meet demand when and if such product is approved.

We may not be able to continue to purchase the materials necessary to produce paclitaxel poliglumex, including paclitaxel, in adequate volume and quality. Paclitaxel is derived from certain varieties of yew trees and the supply of paclitaxel is controlled by a limited number of companies. Paclitaxel is available and we have purchased it from several sources. We purchase the raw materials paclitaxel and polyglutamic acid from a single source on a purchase order basis. Should the paclitaxel or polyglutamic acid purchased from our sources prove to be insufficient in quantity or quality, should a supplier fail to deliver in a timely fashion or at all, or should these relationships terminate, we may not be able to obtain a sufficient supply from alternate sources on acceptable terms, or at all.

Our dependence on third-party manufacturers means that we do not always have direct control over the manufacture, testing or distribution of our products.

We do not currently have internal analytical laboratory or manufacturing facilities to allow the testing or production and distribution of drug products in compliance with cGMPs. Because we do not directly control our suppliers, these vendors may not be able to provide us with finished product when we need it.

We will be dependent upon these third parties to supply us in a timely manner with products manufactured in compliance with cGMPs or similar manufacturing standards imposed by US and/or foreign regulatory authorities where our products will be tested and/or marketed. While the FDA and other regulatory authorities maintain oversight for cGMP compliance of drug manufacturers, contract manufacturers may at times violate cGMPs. The FDA and other regulatory authorities may take action against a contract manufacturer who violates cGMPs. One of our products under development, paclitaxel poliglumex, has a complex manufacturing process, which may prevent us from obtaining a sufficient supply of drug product for the clinical trials and commercial activities currently planned or underway on a timely basis, if at all. The active pharmaceutical ingredients and finished products for pixantrone and brostallicin are both manufactured by a single vendor. The drug substance for Zevalin is produced under contract by Biogen and the drug product and finished product is manufactured and distributed at a contract manufacturer and contract distribution facility.

If we do not successfully develop additional products, we may be unable to generate significant revenue or become profitable.

We divested our commercial product, TRISENOX, in July 2005 and only acquired a new commercial product, Zevalin, in December 2007. Our ability to generate significant revenues from Zevalin is dependent in part on our ability to find new markets for the product, including through gaining wider acceptance and use of the drug by physicians and through FDA approval of expanded uses for the product. There is no guarantee that we will be successful in accomplishing either of these goals. Paclitaxel poliglumex, pixantrone, brostallicin and label expansions for Zevalin are currently in clinical trials and may not be successful. For example, our STELLAR phase III clinical trials for paclitaxel poliglumex for the treatment of non-small cell lung cancer failed to meet their primary endpoints. A number of companies in the pharmaceutical industry, including us, have suffered significant setbacks in advanced clinical trials, even after reporting promising results in earlier trials. We will need to commit significant time and resources to develop this and additional product candidates. Our product candidates will be successful only if:

• our product candidates are developed to a stage that will enable us to commercialize them or sell related marketing rights to pharmaceutical companies;

• we are able to commercialize product candidates in clinical development or sell the marketing rights to third parties; and

• our product candidates, if developed, are approved by the regulatory authorities.

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We are dependent on the successful completion of these goals in order to generate revenues. The failure to generate such revenues may preclude us from continuing our research and development of these and other product candidates.

If we are unable to enter into new licensing arrangements, our future product portfolio and potential profitability could be harmed.

One component of our business strategy is in-licensing drug compounds developed by other pharmaceutical and biotechnology companies or academic research laboratories. Substantially all of our product candidates in clinical development are in-licensed from a third party, including Zevalin, paclitaxel poliglumex, pixantrone, and brostallicin.

Competition for new promising compounds and commercial products can be intense. If we are not able to identify future in-licensing opportunities and enter into future licensing arrangements on acceptable terms, our future product portfolio and potential profitability could be harmed.

We may take longer to complete our clinical trials than we expect, or we may not be able to complete them at all.

Before regulatory approval for any potential product can be obtained, we must undertake extensive clinical testing on humans to demonstrate the safety and efficacy of the product. Although for planning purposes we forecast the commencement and completion of clinical trials, the actual timing of these events can vary dramatically due to a number of factors. On March 4, 2008, we submitted an MAA to the EMEA for paclitaxel poliglumex, however, we do not expect a regulatory decision on an MAA prior to the second half of 2009. Analysis of the data from our EXTEND trial is expected in the second half of 2008 and, if final study results are adequate, we could submit an NDA with the FDA in early 2009 with potential approval in the second half of 2009.

We may not obtain authorization to permit product candidates that are already in the preclinical development phase to enter the human clinical testing phase. Authorized preclinical or clinical testing may not be completed successfully within any specified time period by us, or without significant additional resources or expertise to those originally expected to be necessary. Many drugs in human clinical trials fail to demonstrate the desired safety and efficacy characteristics. Clinical testing may not show potential products to be safe and efficacious and potential products may not be approved for a specific indication. Further, the results from preclinical studies and early clinical trials may not be indicative of the results that will be obtained in later-stage clinical trials. Data obtained from clinical trials are susceptible to varying interpretations. Government regulators and our collaborators may not agree with our interpretation of our clinical trial results. In addition, we or regulatory authorities may suspend clinical trials at any time on the basis that the participants are being exposed to unacceptable health risks or for other reasons. Completion of clinical trials depends on, among other things, the number of patients available for enrollment in a particular trial, which is a function of many factors, including the number of patients with the relevant conditions, the nature of the clinical testing, the proximity of patients to clinical testing centers, the eligibility criteria for tests as well as competition with other clinical testing programs involving the same patient profile but different treatments.

We have limited experience in conducting clinical trials. We expect to continue to rely on third parties, such as contract research organizations, academic institutions and/or cooperative groups, to conduct, oversee and monitor clinical trials as well as to process the clinical results and manage test requests, which may result in delays or failure to complete trials if the third parties fail to perform or to meet the applicable standards.

If we fail to commence or complete, need to perform more or larger clinical trials than planned or experience delays in any of our present or planned clinical trials, our development costs may increase and/or our ability to commercialize our product candidates may be adversely affected. If delays or costs are significant, our financial results and our ability to commercialize our product candidates may be adversely affected.

If we fail to establish and maintain collaborations or if our partners do not perform, we may be unable to develop and commercialize our product candidates.

We have entered into collaborative arrangements with third-parties to develop and/or commercialize product candidates and are currently seeking additional collaborations. For example, we entered into an agreement with the Gynecologic Oncology Group to perform a phase III trial of paclitaxel poliglumex in patients with ovarian cancer. Additional collaborations might be necessary in order for us to fund our research and development activities and third-party manufacturing arrangements, seek and obtain regulatory approvals and successfully commercialize our existing and future product candidates. If we fail to enter into additional collaborative arrangements or fail to maintain our existing collaborative arrangements, the number of product candidates from which we could receive future revenues would decline. For example, in 2005 we sold our product

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TRISENOX to Cephalon and, pursuant to the terms of the purchase agreement under which TRISENOX was sold, we are entitled to receive milestone payments upon the approval by the FDA of new labeled uses for TRISENOX, however, Cephalon may decide not to submit any additional information to the FDA to apply for label expansion of TRISENOX, in which case we would not receive a milestone payment under the agreement.

Our dependence on collaborative arrangements with third parties will subject us to a number of risks that could harm our ability to develop and commercialize products, including that:

• collaborative arrangements may not be on terms favorable to us;

• disagreements with partners may result in delays in the development and marketing of products, termination of our collaboration agreements or time consuming and expensive legal action;

• we cannot control the amount and timing of resources partners devote to product candidates or their prioritization of product candidates and partners may not allocate sufficient funds or resources to the development, promotion or marketing of our products, or may not perform their obligations as expected;

• partners may choose to develop, independently or with other companies, alternative products or treatments, including products or treatments which compete with ours;

• agreements with partners may expire or be terminated without renewal, or partners may breach collaboration agreements with us;

• business combinations or significant changes in a partner’s business strategy might adversely affect that partner’s willingness or ability to complete its obligations to us; and

• the terms and conditions of the relevant agreements may no longer be suitable.

The occurrence of any of these events could adversely affect the development or commercialization of our products.

Because we base several of our drug candidates on unproven novel technologies, we may never develop them into commercial products.

We base several of our product candidates upon novel technologies that we are using to develop drugs for the treatment of cancer. These technologies have not been proven. Furthermore, preclinical results in animal studies may not predict outcomes in human clinical trials. Our product candidates may not be proven safe or effective. If these technologies do not work, our drug candidates may not develop into commercial products.

We are subject to additional legal duties, additional operational challenges and additional political and economic risks related to our operations in Italy.

A portion of our business is based in Italy. We are subject to duties and risks arising from doing business in Italy, such as:

• Italian employment law, including collective bargaining agreements negotiated at the national level and over which we have no control;

• European data protection regulations, under which we will be unable to send private personal data, including many employment records and some clinical trial data, from our Italian offices to our U.S. offices until our U.S. offices self-certify their adherence to the safe harbor framework established by the U. S. Department of Commerce in consultation with the European Commission;

• tariffs, customs, duties and other trade barriers; and

• capital controls, terrorism and other political risks.

We are also subject to the following operational challenges, among others, as a result of having a portion of our business and operations based in Italy:

• effectively pursuing the clinical development and regulatory approvals of all product candidates;

• successfully commercializing products under development;

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• coordinating research and development activities to enhance introduction of new products and technologies;

• coalescing the Italian business culture with our own and maintaining employee morale; and

• maintaining appropriate uniform standards, controls, procedures and policies relating to financial reporting and employment related matters, and the conduct of development activities that comply with both U.S. and Italian laws and regulations.

We may not succeed in addressing these challenges, risks and duties, any of which may be exacerbated by the geographic separation of our operations in the United States and in Italy. These risks related to doing business in Italy could harm the results of our operations.

Because there is a risk of product liability associated with our products, we face potential difficulties in obtaining insurance.

Our business exposes us to potential product liability risks inherent in the testing, manufacturing, marketing and sale of human pharmaceutical products, and we may not be able to avoid significant product liability exposure. While we have insurance covering marketing and sales of Zevalin as well as product use in our clinical trials for our product candidates, it is possible that we will not be able to maintain such insurance on acceptable terms or that any insurance obtained will provide adequate coverage against potential liabilities. Our inability to obtain sufficient insurance coverage at an acceptable cost or otherwise to protect against potential product liability claims could prevent or limit the commercialization of Zevalin or any products we develop. A successful product liability claim in excess of our insurance coverage could exceed our net worth.

Adverse events related to our products can negatively impact our product sales and results from operations.

Our commercial product, Zevalin, has the possibility of causing significant side effects in patients, and deaths associated with an infusion reaction symptom complex, though rare, have occurred within 24 hours of infusions of rituximab, a component of Zevalin. In addition, Yttrium-90 Zevalin administration often results in severe and prolonged cytopenias in most patients, while severe cutaneous and mucocutaneous reactions have also been reported. While side effects are common in oncology drugs, adverse events such as these could negatively impact sales of Zevalin, which in turn could negatively impact our results from operations.

Since we use hazardous materials in our business, we may be subject to claims relating to improper handling, storage or disposal of these materials.

Our research and development activities involve the controlled use of hazardous materials, chemicals and various radioactive compounds. We are subject to international, federal, state, and local laws and regulations governing the use, manufacture, storage, handling and disposal of such materials and certain waste products. Although we believe that our safety procedures for handling and disposing of such materials comply with the standards prescribed by the regulations, the risk of accidental contamination or injury from these materials cannot be eliminated completely. In the event of such an accident, we could be held liable for any damages that result and any such liability not covered by insurance could exceed our resources. Compliance with environmental laws and regulations may be expensive, and current or future environmental regulations may impair our research, development or production efforts.

We may not be able to conduct animal testing in the future, which could harm our research and development activities.

Certain of our research and development activities involve animal testing. Such activities have been the subject of controversy and adverse publicity. Animal rights groups and other organizations and individuals have attempted to stop animal testing activities by pressing for legislation and regulation in these areas and by disrupting activities through protests and other means. To the extent the activities of these groups are successful, our business could be materially harmed by delaying or interrupting our research and development activities.

Our operations in Italy make us subject to increased risk regarding currency exchange rate fluctuations.

As a result of operations in Italy, we are exposed to risks associated with foreign currency transactions insofar as we use U.S. dollars to make contract payments denominated in euros or vice versa. As the net positions of our foreign currency transactions might fluctuate, our earnings might be negatively affected. In addition, we are exposed to risks associated with the translation of euro-denominated financial results and accounts into U.S. dollars. Our reporting currency will remain as the U.S. dollar; however, a portion of our consolidated financial obligations will arise in euros. In addition, the carrying value of some

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of our assets and liabilities will be affected by fluctuations in the value of the U.S. dollar as compared to the euro. Changes in the value of the U.S. dollar as compared to the euro might have an adverse effect on our reported results of operations and financial condition.

Risks Related To the Securities Markets

Our stock price is extremely volatile, which may affect our ability to raise capital in the future and may subject the value of your investment in our securities to sudden decreases.

The market price for securities of biopharmaceutical and biotechnology companies, including ours, historically has been highly volatile, and the market from time to time has experienced significant price and volume fluctuations that are unrelated to the operating performance of such companies. For example, during the twelve month period ended March 19, 2008, our stock price, as adjusted to reflect the one-for-four reverse stock split effected in April 2007, has ranged from a low of $0.47 to a high of $7.56. Fluctuations in the trading price or liquidity of our common stock may adversely affect the value of your investment in our common stock.

Factors that may have a significant impact on the market price and marketability of our securities include:

• announcements by us or others of results of preclinical testing and clinical trials and regulatory actions;

• announcements of technological innovations or new commercial therapeutic products by us, our collaborative partners or our present or potential competitors;

• our issuance of additional debt, equity or other securities, which we need to pursue in 2008 to generate additional funds to cover our current debt and operating expenses;

• our quarterly operating results;

• developments or disputes concerning patent or other proprietary rights;

• developments in our relationships with collaborative partners;

• acquisitions or divestitures;

• litigation and government proceedings;

• adverse legislation, including changes in governmental regulation;

• third-party reimbursement policies;

• changes in securities analysts’ recommendations;

• changes in health care policies and practices;

• economic and other external factors; and

• general market conditions.

In the past, following periods of volatility in the market price of a company’s securities, securities class action litigation has often been instituted. For example, in the case of our company, beginning in March 2005, several class action lawsuits were instituted against CTI and certain directors and officers of CTI and a derivative action lawsuit was filed against CTI’s full board of directors. While these lawsuits were dismissed with prejudice, as a result of these types of lawsuits, we could incur substantial legal fees and our management’s attention and resources could be diverted from operating our business as we respond to the litigation. We maintain significant insurance to cover these risks for the Company and our directors and officers, but our insurance is subject to high deductibles to reduce premium expense, and there is no guarantee that the insurance will cover any specific claim that we may face in the future, or that it will be adequate to cover all potential liabilities and damages,

Our common stock is listed on the Nasdaq Global Market and we may not be able to maintain that listing, which may make it more difficult for investors to sell shares of our common stock.

Our common stock is listed on the Nasdaq Global Market. The Nasdaq Global Market has several quantitative and qualitative requirements companies must comply with to maintain this listing, including a $1.00 minimum bid price per share and $50 million minimum value of listed securities. As of March 20, 2008, our common stock had a closing bid price below

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$1.00 for 13 consecutive days. If our closing bid price remains below $1.00 for 30 consecutive days, under the current Nasdaq Global Market rules we will have a period of 180 days to attain compliance by again meeting the $1.00 minimum bid price. We would then have the option to transfer to the Nasdaq Capital Market, assuming we meet all other initial listing qualifications for the Nasdaq Capital Market, where we can receive an additional 180 days to regain compliance. If we are unable to attain compliance with the minimum bid price we may be delisted. In addition, if we fail to maintain the minimum value of listed securities, we may have to transfer to the Nasdaq Capital Market or may be delisted. The level of trading activity of our common stock may decline if it is no longer listed on the Nasdaq Global Market or Nasdaq Capital Market. Furthermore, our failure to maintain a listing on the Nasdaq market may constitute an event of default under certain of our indebtedness which would accelerate the maturity date of such date. As such, if our common stock ceases to be listed for trading on the Nasdaq Global Market or Nasdaq Capital Market for any reason, it may harm our stock price, increase the volatility of our stock price and make it more difficult to for investors to sell shares of our common stock.

Anti-takeover provisions in our charter documents and under Washington law could make removal of incumbent management or an acquisition of us, which may be beneficial to our shareholders, more difficult.

Provisions of our articles of incorporation and bylaws may have the effect of deterring or delaying attempts by our shareholders to remove or replace management, to commence proxy contests, or to effect changes in control. These provisions include:

• a classified board so that only approximately one third of the board of directors is elected each year;

• elimination of cumulative voting in the election of directors;

• procedures for advance notification of shareholder nominations and proposals;

• the ability of our board of directors to amend our bylaws without shareholder approval; and

• the ability of our board of directors to issue shares of preferred stock without shareholder approval upon the terms and conditions and with the rights, privileges and preferences as the board of directors may determine.

In addition, as a Washington corporation, we are subject to Washington law which imposes restrictions on some transactions between a corporation and certain significant shareholders.

These provisions, alone or together, could have the effect of deterring or delaying changes in incumbent management, proxy contests or changes in control.

Risks Related To Our Notes

The notes will be subordinated to all of our existing and future secured indebtedness.

The notes will be unsecured and effectively subordinated in right of payment to all our existing and future secured indebtedness to the extent of the value of the assets secured by such assets. The notes are equal in right of payment to all of our other existing and future senior debt, including our 6.75% Convertible Senior Notes due 2010, 7.5% Convertible Senior Notes due 2011 and 9% Convertible Senior Notes due 2012. In the event of our bankruptcy, liquidation or reorganization, or upon acceleration of the notes and other existing and future senior debt due to an event of default and in specific other events, our assets will be available to pay obligations on the notes and other existing and future senior debt only after any secured debt has been paid in full. There may not be sufficient assets remaining to pay amounts due on any of the notes that are then outstanding. The incurrence of additional secured or senior debt and other liabilities by us or our subsidiaries could impede our ability to pay obligations on the notes.

We anticipate that from time to time we will incur additional debt, including senior indebtedness. See “Description of Notes—Ranking.”

We may not have sufficient funds to repurchase or redeem the notes.

At maturity, the entire outstanding principal amount of the notes and any accrued and unpaid interest will become due and payable. If we experience a change in control, each holder of the notes may require us to repurchase all or a portion of that holder’s notes. Upon any such repurchase of the notes in connection with a non-stock change of control or upon any automatic conversion of the notes, we will be required to pay holders of the notes repurchased or converted a make-whole payment in an amount equal to $115 per $1,000 principal amount of the notes less the amount of interest paid on such notes prior to the repurchase date or conversion date. Payment of principal at maturity must be in cash, while any make-whole payment or payment to repurchase notes in the event of a change of control may be made in cash, common stock or some combination of

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cash and common stock. At maturity, upon automatic conversion or if we experience a change in control and are unable to make any required payment in common stock, we may not have sufficient funds or may be unable to arrange for additional financing to pay the principal amount or repurchase price due on the notes then outstanding.

In addition, our borrowing arrangements or agreements relating to senior debt to which we become a party may contain restrictions on, or prohibitions against, our repurchases or redemptions of the notes. If the maturity date or change in control occurs at a time when our other arrangements prohibit us from repurchasing or redeeming the notes, we could try to obtain the consent of the lenders under those arrangements to purchase the notes, or we could attempt to refinance the borrowings that contain the restrictions. If we do not obtain the necessary consents or refinance these borrowings, we will be unable to repurchase or redeem the notes. In that case, our failure to repurchase or redeem any tendered notes or notes due upon maturity would constitute an event of default under the indenture governing the notes and other indebtedness. Any such default, in turn, may cause a default under the terms of our senior debt.

We may be unable to generate sufficient cash flow from which to make payments on the notes.

We expect to incur substantial net operating losses for the foreseeable future. We may not become profitable or sustain profitability in the future. Accordingly, if we are unable to make payments in common stock pursuant to the indenture or otherwise, we may not have sufficient funds to make payments on the notes.

There is no public market for the notes which may significantly impair the liquidity of the notes.

The notes were sold to the initial purchasers pursuant to an exemption from registration under the Securities Act and applicable state or foreign securities laws and neither the notes nor the common stock issuable upon conversion of the notes may be resold by purchasers unless the notes and the common stock issuable upon conversion of the notes are subsequently registered under the Securities Act or an exemption for the registration requirements of the Securities Act and applicable estate or foreign securities laws is available for such resale.

Prior to the sale of the notes offered by this prospectus, there has been no public market for any of the notes offered by this prospectus, and there can be no assurance as to:

• the liquidity of any such market that may develop

• the ability of the holders to sell their notes or

• the price at which the holder would be able to sell their notes

If such a market were to exist, the notes could trade at prices that may be higher or lower than the principal amount or purchase price, depending on many factors, including prevailing interest rates, the market for similar notes, and our financial performance. We do not presently intend to apply for the listing of the notes on any securities exchange.

The notes may not be rated or may receive a lower rating than anticipated.

We believe it is unlikely that the notes will be rated. However, if one or more rating agencies rate the notes and assign the notes a rating lower than the rating expected by investors, or reduce the rating of the notes in the future, the market price of the notes and our common stock may be adversely affected.

If you convert any notes, the value of the common stock you receive may fluctuate significantly.

The market price of our common stock has fluctuated significantly and may continue to do so in the future. For the twelve month period ended March 19, 2008, our stock price, as adjusted to reflect the one-for-four reverse stock split effected in April 2007, ranged from a low of $0.47 to a high of $7.56. Because the notes are convertible into shares of common stock, fluctuations in the stock price may affect the trading price of the notes. The risk of price fluctuations of our common stock also applies to holders who receive shares of common stock upon conversion of the notes. Significant fluctuations in the market price of our common stock underlying the notes may occur in response to various factors and events, including, among other things:

• the depth and liquidity of the trading market for or our common stock;

• quarterly variations in our actual or anticipated operating results;

• changes in estimates of our financial results and prospects by securities analysts;

• market conditions in the drug industry;

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• announcements and performance by our competitors;

• regulatory actions; and

• general economic conditions

In the past, our common stock has experienced volatility not necessarily related to announcements of our financial performance. Broad market fluctuations may also adversely affect the market price of the underlying common stock.

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USE OF PROCEEDS

All 5.75% Senior Convertible Notes and shares of our common stock offered by this prospectus are being registered for the account of the selling securityholders. We will not receive any of the proceeds from the sale of these securities.

DESCRIPTION OF CAPITAL STOCK

This summary does not purport to be complete and is subject to, and qualified in its entirety by, the provisions of our Amended and Restated Articles of Incorporation and all applicable provisions of Washington law.

General

We are authorized to issue 200,000,000 shares of common stock, no par value, and 10,000,000 shares of preferred stock, no par value. As of the close of business on March 25, 2008, there were 94,634,431 shares of common stock issued and outstanding. We also had 550 shares of our Series A 3% convertible preferred stock outstanding, 5,218 shares of our Series B 3% convertible preferred stock outstanding, 6,284 shares of our Series C 3% convertible preferred stock outstanding and 1,000 shares of our Series D 7% convertible preferred stock outstanding as of March 25, 2008.

Common Stock

Each holder of common stock is entitled to one vote for each share held on all matters to be voted upon by the shareholders and there are no cumulative voting rights. Subject to preferences that may be applicable to any outstanding preferred stock, holders of common stock are entitled to receive ratably the dividends, if any, that are declared from time to time by the board of directors out of funds legally available for that purpose. In the event of a liquidation, dissolution or winding up of the company, the holders of common stock are entitled to share in our assets remaining after the payment of liabilities and the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock. Holders of common stock have no preemptive or conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to the common stock. All outstanding shares of common stock are fully paid and nonassessable. The rights, preferences and privileges of the holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate in the future.

Preferred Stock

The board of directors has the authority, without action by the shareholders, to designate and issue preferred stock in one or more series and to designate the rights, preferences and privileges of each series, which may be greater than the rights of the common stock. It is not possible to state the actual effect of the issuance of any shares of preferred stock upon the rights of holders of the common stock until the board of directors determines the specific rights of the holders of this preferred stock. However, the effects might include, among other things:

• Restricting dividends on the common stock;

• diluting the voting power of the common stock;

• impairing the liquidation rights of the common stock;

• delaying or preventing a change in control of the company without further action by the shareholders.

As of March 25, 2008, 550 shares of our Series A 3% convertible preferred stock were outstanding, 5,218 shares of our Series B 3% convertible preferred stock were outstanding, 6,284 shares of our Series C 3% convertible preferred stock were outstanding and 1,000 shares of our Series D 7% convertible preferred stock were outstanding.

Anti-takeover Effects of Provisions of Washington Law and our Charter and Bylaws

Washington law contains certain provisions that may have the effect of delaying, deterring or preventing a change in control of the company. Chapter 23B.17 of the Washington Business Corporation Act (the WBCA) prohibits, subject to certain exceptions, a merger, sale of assets or liquidation of the company involving an “interested shareholder” (defined as a person or group of affiliated persons who own beneficially 20% or more of the company’s voting securities) unless the transaction is determined to be at a “fair price” or otherwise approved by a majority of the company’s disinterested directors or is approved by holders of two-thirds of the company’s outstanding voting securities, other than those held by the interested shareholder. A Washington corporation may, in its articles of incorporation, exempt itself from coverage of this provision, but the company has not done so. In addition, Chapter 23B.19 of the WBCA prohibits the company, with certain exceptions, from engaging in certain significant business transactions with an “acquiring person” (defined as a person or group of persons who acquire 10%

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or more of the company’s voting securities without the prior approval of the company’s board of directors) for a period of five years following the acquiring person’s share acquisition date. The prohibited transactions include, among others, a merger or consolidation with, disposition of assets to, or issuance or redemption of stock to or from, the acquiring person, or otherwise allowing the acquiring person to receive any disproportionate benefit as a shareholder. The company may not exempt itself from coverage of this statute. These statutory provisions may have the effect of delaying, deterring or preventing a change in control of the company.

Our board of directors is divided into three approximately equal classes of directors serving staggered three-year terms. In addition, our Amended and Restated Articles of Incorporation provide that directors may be removed from office only at a meeting of shareholders called expressly for that purpose and only for cause. Our Amended and Restated Articles of Incorporation limit “cause” to willful misfeasance having a material adverse effect on the company or conviction of a felony, provided that any action by a director shall not constitute “cause” if, in good faith, the director believed the action to be in or not opposed to the best interests of the company or if the director is entitled to be indemnified with respect to such action under applicable law, our Amended and Restated Articles of Incorporation or Amended and Restated Bylaws, or a contract with the company. Further, our Amended and Restated Bylaws require a shareholder to provide notice to the company of such shareholder’s intent to nominate a person or persons for election as directors not later than 90 days prior to the first anniversary of the previous year’s annual meeting of shareholders or, in the case of an election to be held at a special meeting of shareholders for the election of directors, the close of business on the tenth day following the date on which notice of such meeting is first given to shareholders. A shareholder must also provide us with notice of such shareholder’s intent to make any proposal at an annual meeting of shareholders not later than 90 days prior to the first anniversary of the previous year’s annual meeting of shareholders. These provisions may have the effect of deterring hostile takeovers or delaying change in control or management of our company.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Computershare Investor Services, LLC.

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DESCRIPTION OF NOTES

The 5.75% Convertible Senior Notes due December 15, 2011 are issued under, and are governed by, an indenture, between us and U.S. Bank National Association, as trustee. Because this section is a summary, it does not describe every aspect of the notes, the indenture or the registration rights agreement. This summary is subject to, and qualified in its entirety by, reference to all the provisions of the indenture and the registration rights agreement, including definitions of certain terms used in the indenture or the registration rights agreement.

General

Ranking. The notes are part of our general, unsecured obligations. The notes are senior in right of payment, which means that they rank in right of payment equal to certain of our indebtedness, including our 6.75% Convertible Senior Notes due 2010, 7.5% Convertible Senior Notes due 2011 and 9% Convertible Senior Notes due 2012, but are senior in right of payment to our 5.75% Convertible Subordinated Notes due 2008, our 5.75% Convertible Senior Subordinated Notes due 2008 and our 4% Convertible Senior Subordinated Notes due 2010. The notes will mature after our 6.75% Convertible Senior Notes due 2010 and our 7.5% Convertible Senior Notes due 2011. We are required to repay the full principal amount of the notes on December 15, 2011, unless they are previously converted, redeemed or repurchased.

Interest. The notes bear interest at the rate of 5.75% per annum from the date of issuance of the notes. We will pay interest twice a year, on each June 15 and December 15, beginning June 15, 2008, until the principal is paid or made available for payment or the notes have been converted. We will pay interest to the persons in whose name the note is registered at the close of business on the immediately preceding June 1 or December 1, as the case may be, which we refer to as a regular record date. Interest will be calculated on the basis of a 360-day year consisting of twelve 30-day months.

Interest on the notes is payable, at our option, in cash, common stock or some combination of cash and common stock having a fair market value equal to the interest payment due. For the purposes of payment in common stock, the fair market value of our common stock shall be equal to 95% of its volume-weighted average price for the five consecutive trading days ending on the trading day immediately preceding the interest payment date. Any such payment in common stock shall be in compliance with Nasdaq shareholder approval rules.

Conversion. Holders may convert the notes into shares of our common stock at any time before the close of business on December 15, 2011, unless the notes have been previously redeemed or repurchased. The initial conversion rate for the notes is 333.333 shares of common stock per $1,000 principal amount of notes. This conversion rate is equivalent to a conversion price of $3.00 per share. The conversion rate is subject to adjustment as described below. Holders of notes submitted for redemption are entitled to convert the notes up to and including the business day immediately preceding the date fixed for redemption.

Optional Redemption. Prior to December 15, 2009, we will not have the right to redeem any notes at our option. On or after December 15, 2009, we shall have the right to redeem some or all of the notes for cash at any time. Such redemption will be at a price equal to the par value of the notes plus a Make-Whole Payment and accrued and unpaid interest to, but not including, the redemption date.

Automatic Conversion. Subject to certain conditions, the notes will automatically convert if, at any time after December 15, 2009, and prior to maturity, the closing price per share of our common stock has exceeded 140% of the conversion price then in effect for at least 20 trading days within any 30-consecutive trading day period.

Repurchase Upon Change in Control. If we experience a change in control, as described below, you will have the right to require us to repurchase your notes as described below under “Repurchase at Option of Holders Upon a Change in Control.”

Make-Whole Payments. Upon any automatic conversion of the notes, if a holder exercises their right to require us to repurchase their notes in connection with a non-stock change of control (as defined in the indenture) or we elect to redeem any of the notes, we will pay to the holder an amount equal to $115 per $1,000 principal amount of the notes so converted, repurchased or redeemed less the amount of any interest paid on such notes prior to the conversion or repurchase date. This payment may be made in cash, common stock or some combination of cash and common stock having a fair market value equal to the interest payment due. For the purposes of payment in common stock, the fair market value of our common stock shall be equal to 95% of its volume-weighted average price for the five consecutive trading days ending on the trading day immediately preceding the conversion or repurchase date. Any such payment in common stock shall be in compliance with Nasdaq shareholder approval rules.

Sinking Fund. No “sinking fund” is provided for the notes, which means that the indenture does not require us to redeem or retire the notes periodically.

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Form, Denomination, Transfer, Exchange and Book-Entry Procedures

The notes are issued:

• only in fully registered form;

• without interest coupons; and

• in denominations of $1,000 and integral multiples thereof.

Principal of, premium, if any, and interest on the notes will be payable, and the notes may be presented for registration or exchange, at the office or agency we maintain for such purpose in the Borough of Manhattan, The City of New York. Until we designate otherwise, our office or agency will be the trustee’s corporate trust office presently located in the Borough of Manhattan, The City of New York.

The notes are currently evidenced by one or more global notes that are deposited with the trustee as custodian for DTC and registered in the name of Cede & Co., as nominee of DTC. Except as set forth below, record ownership of the global note may be transferred, in whole or in part, only to another nominee of DTC or to a successor of DTC or its nominee.

The global note is not registered in the name of any person, nor can it be exchanged for notes that are registered in the name of any person, other than DTC or its nominee, unless either of the following occurs:

• DTC has notified us that it is unwilling or unable to continue as depository for the global note or has ceased to be a clearing agency registered as such under the Exchange Act or announces an intention permanently to cease business or does in fact do so; or

• an event of default with respect to the notes represented by the global note has occurred and is continuing.

In those circumstances, DTC will determine in whose names any notes issued in exchange for the global note will be registered.

So long as the notes are registered in the name of Cede & Co. as nominee for DTC, DTC or its nominee will be considered the sole owner and holder of the global note for all purposes, and as a result:

• you cannot receive notes registered in such holder’s name if they are represented by the global notes;

• you cannot receive certificated (physical) notes in exchange for their beneficial interest in the global notes;

• you will not be considered to be the owner or holder of the global note or any note it represents for any purpose; and

• all payments on the global note will be made to DTC or its nominee.

The laws of some jurisdictions require that certain kinds of purchasers can only own securities in physical, certificated form. These laws may limit your ability to acquire interest in the notes and to transfer or encumber your beneficial interests in the global note to these types of purchasers.

Only institutions, such as a securities broker or dealer, that have accounts with DTC or its nominee, called participants, and persons that may hold beneficial interests through participants can own a beneficial interest in the global note. The only place where the ownership of beneficial interests in the global note appears and the only way the transfer of those interests can be made is on the records kept by DTC (for its participants’ interests) and the records kept by those participants (for interests participants hold on behalf of other persons).

Secondary trading in bonds and notes of corporate issuers is generally settled in clearinghouse (that is, next day) funds. In contrast, beneficial interests in a global note usually trade in DTC’s same day funds settlement system, and settle in immediately available funds. We make no representation as to the effect that settlement in immediately available funds will have on trading activity in those beneficial interests.

So long as DTC through Cede & Co. is the sole registered holder of the notes, we will make payments of interest on, and the redemption or repurchase price of, the global note only to Cede & Co., the nominee for DTC, as the registered owner of the global notes. We will make these payments by wire transfer of immediately available funds or in shares of Common Stock on each payment date.

We understand that, with respect to any payment of interest on, principal of, or repurchase price of, the global note, DTC’s practice is to credit participants’ accounts on the payment date with payments in amounts proportionate to their respective beneficial interests in the notes represented by the global note as shown on DTC’s records, unless DTC has reason to believe that it will not receive payment on that payment date. Payments by participants to owners of beneficial interests in notes represented by the global notes held through participants are the responsibility of those participants, as is now the case with securities held for the accounts of customers registered in “street name.”

We also understand that neither DTC nor Cede & Co. will consent or vote with respect to the notes. We have been advised that under its usual procedures, DTC will mail an “omnibus proxy” to us as soon as possible after the record date. The omnibus proxy assigns Cede & Co.’s consenting or voting rights to those participants to whose accounts the notes are credited on the record date identified in a listing attached to the omnibus proxy.

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Because DTC can only act on behalf of participants, who in turn act on behalf of indirect participants, the ability of a person having a beneficial interest in the principal amount represented by the global note to pledge or otherwise encumber their interest in the note to persons or entities that do not participate in the DTC book entry system, or otherwise take actions in respect of that interest, may be adversely affected by the lack of a physical certificate evidencing its interest.

We understand that DTC will take any action permitted to be taken by a holder of notes (including the presentation of notes for exchange) only at the direction of one or more participants to whose account with DTC interests in the global note are credited and only in respect of such portion of the principal amount of the notes represented by the global note as to which such participant has, or participants have, given such direction.

We also understand that DTC is:

• a limited purpose trust company organized under the laws of the State of New York;

• a member of the Federal Reserve System;

• a “clearing corporation” within the meaning of the Uniform Commercial Code, as amended; and

• a “clearing agency” registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934.

DTC was created to hold securities for its participants and to facilitate the clearance and settlement of securities transactions between participants through electronic book-entry changes in accounts of its participants. Participants include securities brokers and dealers, banks, trust companies and clearing corporations and may include certain other organizations. Certain of such participants (or their representatives), together with other entities, own DTC. Indirect access to the DTC system is available to other entities such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly.

DTC’s policies and procedures, which may change periodically, will apply to payments, transfers, exchanges and other matters relating to beneficial interests in the global note. The trustee and we have no responsibility or liability for any aspect of DTC’s or any participant’s records relating to beneficial interests in the global note, including for payments made on the global note, and we and the trustee are not responsible for maintaining, supervising or reviewing any of those records.

Conversion Rights

You may, at your option, convert the principal amount of any note that is an integral multiple of $1,000 into shares of our common stock at any time prior to the close of business on the maturity date, unless the note has been previously redeemed or repurchased. If the notes are called for redemption, you may convert your notes at any time before the close of business on the business day immediately preceding the date fixed for redemption. In each case, the initial conversion rate is equal to 333.333 shares per $1,000 principal amount of notes, which is equivalent to a conversion price of $3.00 per share. The conversion rate is subject to adjustment as described below.

You can convert the note by delivering the note to the trustee’s corporate trust office, accompanied by a duly signed and completed notice of conversion, a copy of which is attached to the indenture and may be obtained from the trustee. In the case of a global note, we have been informed that DTC will effect the conversion upon notice from the holder of a beneficial interest in the global note in accordance with DTC’s rules and procedures. The conversion date will be the date on which the note and the duly signed and completed notice of conversion are so delivered to the trustee. As promptly as practicable on or after the conversion date, we will issue and deliver to the trustee a certificate or certificates for the number of full shares of common stock issuable upon conversion, together with payment in lieu of any fractional shares, and the trustee shall deliver the certificate(s) to the conversion agent for delivery to the holder of the note being converted. The shares of our common stock issuable upon conversion of the notes will be fully paid and nonassessable.

If you surrender a note for conversion on a date that is not an interest payment date, you will not be entitled to receive any interest for the period from the preceding interest payment date to the date of conversion, except as described below. However, if you are a holder of a note on a regular record date, including a note that is subsequently surrendered for conversion after the regular record date, you will receive the interest payable on such note on the next interest payment date. To correct for this resulting overpayment of interest, we will require that any note surrendered for conversion during the period from the close of business on a regular record date to the opening of business on the next interest payment date be accompanied by payment of an amount equal to the interest payable on such interest payment date on the principal amount of notes being surrendered for conversion. However, you will not be required to make that payment if you are converting a note, or a portion of a note, that we have called for redemption, or that you are entitled to require us to repurchase from you, if your conversion right would terminate because of the redemption or repurchase between the regular record date and the close of business on the next interest payment date.

In addition, if we distribute rights or warrants (other than those referred to in clause (2) below) pro rata to holders of common stock, so long as any such rights or warrants have not expired or been redeemed by us, the holder of any note surrendered for conversion will be entitled to receive upon such conversion, in addition to the shares of common stock issuable

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upon such conversion (which we refer to in this prospectus as the “conversion shares”), a number of rights or warrants to be determined as follows:

• if such conversion occurs on or prior to the date for the distribution to the holders of rights or warrants of separate certificates evidencing such rights or warrants (which we refer to in this prospectus as the “distribution date”), the same number of rights or warrants to which a holder of a number of shares of common stock equal to the number of conversion shares is entitled at the time of such conversion in accordance with the terms and provisions of, and applicable to, the rights or warrants; and

• if such conversion occurs after such distribution date, the same number of rights or warrants to which a holder of the number of shares of common stock into which such note was convertible immediately prior to such distribution date would have been entitled on such distribution date in accordance with the terms and provisions of, and applicable to, the rights or warrants.

No other payment or adjustment for interest, or for any dividends on our common stock, will be made upon conversion. If you receive common stock upon conversion of a note, you will not be entitled to receive any dividends payable to holders of common stock as of any record date before the close of business on the conversion date. We will not issue fractional shares upon conversion of notes. Instead, we will pay an amount in cash based on the closing sales price of our common stock on the conversion date.

If you deliver a note for conversion, you are not required to pay any taxes or duties in respect of the issuance or delivery of common stock on conversion. However, you are required to pay any tax or duty that may be payable in respect of any transfer involved in the issuance or delivery of our common stock in a name other than yours. We will not issue or deliver certificates representing shares of common stock unless the person requesting the issuance or delivery has paid to us the amount of any such tax or duty or has established to our satisfaction that no such tax or duty is payable.

The conversion rate is subject to adjustment if, among other things:

(1) there is a dividend or other distribution payable in common stock on shares of our common stock;

(2) we issue to all holders of common stock rights, options or warrants entitling them to subscribe for or purchase common stock at less than the then current market price, calculated as described in the indenture, of our common stock; however, if those rights, options or warrants are only exercisable upon the occurrence of specified triggering events, then the conversion rate will not be adjusted until the triggering events occur;

(3) we subdivide, reclassify or combine our common stock;

(4) we distribute to all holders of our common stock evidences of our indebtedness, shares of capital stock, cash or assets, including securities, but excluding:

• those dividends, rights, options, warrants and distributions referred to in paragraphs (1) and (2) above;

• dividends and distributions paid in cash (except as set forth in paragraphs (5) and (6) below); and

• distributions upon a merger or consolidation as discussed below;

(5) we make a distribution consisting exclusively of cash (excluding portions of distributions referred to in clause (4) above and cash distributed upon a merger or consolidation as discussed below) to all holders of our common stock if the aggregate amount of the distribution combined together with (A) other such all cash distributions to all holders of our common stock made within the preceding 365-day period in respect of which no adjustment has been made and (B) any cash and the fair market value of other consideration payable in respect of any tender offer by us or any of our subsidiaries for our common stock concluded within the preceding 365-day period in respect of which no adjustment has been made, exceeds 10% of our market capitalization, being the product of the current market price per share of our common stock on the record date for such distribution and the number of shares of common stock then outstanding; or

(6) the successful completion of a tender offer made by us or any of our subsidiaries for our common stock that involves aggregate consideration that, together with (A) any cash and the fair market value of other consideration payable in a tender offer by us or any of our subsidiaries for our common stock concluded within the 365-day period preceding the completion of such tender offer in respect of which no adjustment has been made and (B) the aggregate amount of any such all cash distributions referred to in paragraph (5) above to all holders of common stock within the 365-day period preceding the expiration of such tender offer in respect of which no adjustments have been made, exceeds 10% of our market capitalization on the expiration of such tender offer.

To the extent that our rights plan is still in effect, upon conversion of the notes into common stock, the holders will receive, in addition to the common stock, the rights described in our rights plan, whether or not the rights have separated from the common stock at the time of conversion, subject to certain limited exceptions. See the section of this prospectus entitled “Description of Capital Stock” for more information. If we implement a new rights plan, we are required under the indenture to

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provide that the holder of notes receives the rights upon conversion of the notes, whether or not these rights were separated from the common stock prior to conversion, subject to certain limited exceptions.

We reserve the right to make such increases in the conversion rate in addition to those required by the provisions described above as we may consider to be advisable so that any event treated for United States federal income tax purposes as a dividend of stock or stock rights will not be taxable to the recipients. We are not required to make any adjustment to the conversion rate until the cumulative required adjustments amount to 1.0% or more of the conversion rate. We will compute any adjustments to the conversion rate and give notice to the holders of any such adjustments.

If we merge into or consolidate with another person or sell or transfer all or substantially all of our assets, each note then outstanding will, without the consent of the holder of any note, become convertible only into the kind and amount of securities, cash and other property receivable upon such consolidation, merger, sale or transfer by a holder of the number of shares of common stock into which the note was convertible immediately prior to the merger, consolidation or sale. This calculation will be made based on the assumption that the holder of common stock failed to exercise any rights of election that the holder may have had to select a particular type of consideration. The adjustment will not be made for a merger that does not result in any reclassification, conversion, exchange or cancellation of our common stock.

Ranking

The payment of the principal of, and premium, if any, and interest on the notes, and any amounts payable upon the repurchase of the notes, is equal in right of payment to the extent set forth in the indenture to the payment of our senior debt, as defined in the indenture.

With respect to the notes, “senior debt” means the principal of, and premium, if any, and interest, including all interest accruing subsequent to the commencement of any bankruptcy or similar proceeding, whether or not a claim for post-petition interest is allowable as a claim in any such proceeding, on, and rent payable on or in connection with and all fees, costs, claims, expenses and other amounts payable in connection with, the following, whether absolute or contingent, secured or unsecured, due or to become due, outstanding on the date of the indenture or thereafter created, incurred or assumed:

• our 6.75% Convertible Senior Notes due 2010;

• our 7.5% Convertible Senior Notes due 2011;

• our 9% Convertible Senior Notes due 2012;

• all our indebtedness evidenced by a credit or loan agreement, note, bond, debenture or other similar instrument whether or not the recourse of the lender is to all of our assets or to only a portion;

• all of our indebtedness, obligations and other liabilities, contingent or otherwise, for borrowed money, including, without limitation, overdrafts, foreign exchange contracts, currency exchange agreements, interest rate protection agreements and any loans or advances from banks, whether or not evidenced by notes or similar instruments;

• bonds, debentures, notes or similar instruments, whether or not the recourse of the lender is to all of our assets or to only a portion thereof;

• all our obligations as lessee under leases required to be capitalized on the balance sheet of the lessee under generally accepted accounting principles;

• all our obligations and other liabilities, contingent or otherwise, under any lease or related document, including a purchase agreement, in connection with the lease of real property or improvements, or any personal property included as part of any such lease, which provides that we are contractually obligated to purchase or cause a third party to purchase the leased property and thereby guarantee a residual value of leased property to the lessor and all of our obligations under such lease or related document to purchase or to cause a third party to purchase the leased property, whether or not such lease transaction is characterized as an operating lease or capitalized lease in accordance with generally accepted accounting principles;

• all our obligations under interest rate and currency swaps, caps, floors, collars, hedge agreements, forward contracts or similar agreements or arrangements;

• all our obligations with respect to letters of credit, bank guarantees, bankers’ acceptances and similar facilities, including related reimbursement obligations;

• all our obligations issued or assumed as the deferred purchase price of property or services, but excluding trade accounts payable and accrued liabilities arising in the ordinary course of business;

• all our obligations of the type referred to above of another person and all dividends of another person, the payment of which, in either case, we have assumed or guaranteed, or for which we are responsible or liable, directly or indirectly, jointly or severally, as obligor, guarantor or otherwise, or which are secured by a lien on our property; and

• renewals, extensions, modifications, replacements, restatements and refundings of, or any indebtedness or obligation issued in exchange for any indebtedness or obligation described in the bullets above.

Senior debt does not include:

• our 5.75% Convertible Subordinated Notes due 2008;

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• our 5.75% Convertible Senior Subordinated Notes due 2008;

• our 4% Convertible Senior Subordinated Notes due 2010;

• any indebtedness or obligation if the terms of the indebtedness or obligation, or the terms of the instrument under which the indebtedness or obligation is issued, expressly provide that the indebtedness or obligation is not superior in right of payment to the notes;

• accounts payable or other accrued liability or obligation incurred in the ordinary course of business in connection with the obtaining of materials or services; or

• any indebtedness or obligation that we may owe to any of our direct or indirect subsidiaries.

The notes are effectively senior to all liabilities, including trade payables and lease obligations, and preferred stock of any of our subsidiaries.

The indenture limits our ability and the ability of our subsidiaries to incur certain future indebtedness.

Negative Covenants

We have agreed that we will not, and will not permit any of our subsidiaries to, incur or suffer to exist (i) any indebtedness that is structurally senior or senior by its terms to these notes, or (ii) secured indebtedness, in an aggregate principal amount for both clauses (i) and (ii) exceeding $10,000,000 unless, in the case of secured indebtedness, these notes are equally and ratably secured with such secured indebtedness; provided, however, that liens or encumbrances in favor of strategic partners granted in connection with biopharmaceutical licensing and/or partnering arrangements are not subject to this restriction.

Optional Redemption

Prior to December 15, 2009, we will not have the right to redeem the notes at our option. On or after December 15, 2009, we may redeem the notes in whole or in part in cash at any time prior to maturity at a redemption price equal to $1,000 per $1,000 principal amount of notes to be redeemed plus a Make-Whole Payment and accrued and unpaid interest (including any additional interest then due under the registration rights agreement) to, but not including, the redemption date. The Company or the trustee on its behalf shall give notice not less than five (5) business days prior to the redemption date.

Automatic Conversion

Subject to certain conditions, all of the notes then outstanding will automatically convert if, at any time after December 15, 2009 and prior to maturity, the closing price per share of our common stock has exceeded 140% of the conversion price then in effect for at least 20 trading days within any 30-consecutive trading day period. We will deliver a notice of automatic conversion to the holders not more than 30 days but not less than 20 days prior to the automatic conversion date.

We may only effect an automatic conversion if the shares issuable upon such automatic conversion of the notes are freely transferable pursuant to the requirements of the Securities Act.

Repurchase at Option of Holders Upon a Change in Control

If a change in control occurs, you will have the right, at your option, to require us to repurchase all of your notes not called for redemption, or any portion of the principal amount of your notes that is equal to $1,000 or any greater integral multiple of $1,000. The price we are required to pay is 100% of the principal amount of the notes to be repurchased, together with a Make-Whole Payment and interest accrued (including any additional interest then due under the registration rights agreement), if any, to, but excluding, the repurchase date.

At our option, instead of paying the repurchase price in cash, we, or the successor entity in the change in control transaction, may pay the repurchase price in cash, common stock or in a combination of cash and common stock, such common stock to be equal to 95% of the average of the volume weighted average price per share of our common stock for the five consecutive trading days ending on the trading day immediately preceding the repurchase date. We may only pay the repurchase price in common stock if the conditions provided in the indenture are satisfied. Because the number of shares of common stock to be delivered to holders of notes in payment of the repurchase price (should we elect such payment option) is determined on the basis of the market price of our common stock after we have given notice of the occurrence of the change in control and prior to the repurchase date, the value of the shares of common stock on the date of delivery thereof to such holders may be more or less than the repurchase price had we elected to pay such price in cash. Any such payment in common stock shall be in compliance with Nasdaq shareholder approval rules.

Within 30 days after the occurrence of a change in control, we or the trustee will mail you notice of the change in control and of your repurchase right arising as a result of the change in control. We will also deliver a copy of this notice to the trustee. To exercise the repurchase right, you must deliver, on or before the 30th day (or such greater period as may be required by applicable law) after the date of our notice, irrevocable written notice to the trustee of your exercise of your repurchase right,

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together with the notes with respect to which that right is being exercised. We are required to make the repurchase on a date that is no later than 45 days after your notice to the trustee.

A change in control will be deemed to have occurred at such time, after the original issuance of the notes, any of the following occurs:

• any person acquires beneficial ownership, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of shares of Cell Therapeutics, Inc.’s capital stock entitling that person to exercise more than 33% of the total voting power of all shares of Cell Therapeutics, Inc.’s capital stock entitled to vote generally in elections of directors; however, any acquisition by Cell Therapeutics, Inc., any of its subsidiaries or any of our employee benefit plans will not trigger this provision;

• any person succeeds in having sufficient of its nominees (who are not supported by a majority of the then current board of directors) elected to the board of directors of Cell Therapeutics, Inc. such that such nominees, when added to any existing directors remaining on the board of directors after such election who are affiliates of or acting in concert with such person, shall constitute a majority of the board of directors;

• Cell Therapeutics, Inc. consolidates with or merges with or into any other person or another person merges into Cell Therapeutics, Inc., except if the transaction satisfies any of the following:

• the transaction is a merger (1) that does not result in any reclassification, conversion, exchange or cancellation of outstanding shares of Cell Therapeutics, Inc.’s capital stock and (2) pursuant to which holders of Cell Therapeutics, Inc.’s common stock immediately prior to the transaction have, directly or indirectly, 67% or more of the total voting power of all shares of capital stock or other ownership interest of the continuing or surviving person entitled to vote generally in elections of directors of the continuing or surviving person immediately after the transaction; or

• the transaction is a merger effected only to change Cell Therapeutics, Inc.’s jurisdiction of incorporation and it results in a reclassification, conversion or exchange of outstanding shares of Cell Therapeutics, Inc.’s common stock only into shares of common stock of Cell Therapeutics, Inc. or another corporation;

• Cell Therapeutics, Inc. conveys, transfers, sells, leases or otherwise disposes of all or substantially all of its assets to another person.

The definition of change in control includes a phrase relating to the conveyance, transfer, sale, lease or disposition of all or substantially all of Cell Therapeutics, Inc.’s assets. There is no precise, established definition of the phrase “substantially all” under applicable law. Accordingly, your ability to require us to repurchase your notes as a result of conveyance, transfer, sale, lease or other disposition of less than all of Cell Therapeutics, Inc.’s assets may be uncertain.

The provisions relating to the repurchase at the option of the holders upon a change of control would not necessarily provide you with protection if we are involved in a highly leveraged or other transaction that may adversely affect you.

Our ability to repurchase notes upon the occurrence of a change in control is subject to important limitations. Some of the events constituting a change in control could cause an event of default or be prohibited or limited by the terms of senior debt. As a result, we may not have sufficient cash available to repay such senior debt and repurchase the notes in cash, absent a waiver. Further, we may not have the financial resources, or would be unable to arrange financing, to pay the repurchase price for all the notes that holders seeking to exercise their repurchase right deliver to us. If we were to fail to repurchase the notes when required following a change in control, an event of default would occur under the indenture. Any such default may, in turn, cause a default under any then outstanding senior debt.

We may also at our option, to the extent permitted by applicable law, at any time purchase notes in the open market or by tender or by private agreement. Any note that we so purchase may, to the extent permitted by applicable law, be reissued or resold or may, at our option, be surrendered to the trustee for cancellation. Any notes surrendered may not be reissued or resold and will be canceled promptly.

Make-Whole Payment

Upon any automatic conversion of the notes, if you exercise your right to require us to repurchase your notes in connection with a non-stock change of control or we elect to redeem any notes, we will pay to you an amount equal to $115 per $1,000 principal amount of your notes so converted, repurchased or redeemed less the amount of any interest paid on such notes prior to the conversion or repurchase date. This payment may be made in cash, common stock or some combination of cash and common stock. For the purposes of this provision, the fair market value of our common stock shall be equal to 95% of its volume-weighted average price for the five consecutive trading days ending on the trading day immediately preceding the conversion or repurchase date. No make-whole amount shall be payable upon any conversion, repurchase or redemption of the notes other than in connection with an automatic redemption of the notes, repurchase of the notes in connection with a non-stock change of control as set forth in the indenture governing the notes or optional redemption at our election.

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Mergers and Sales of Assets

Without the consent of the holders of the notes, Cell Therapeutics, Inc. may not consolidate with or merge into any other person, or convey, transfer, sell or lease its properties and assets substantially as an entirety to any person, and Cell Therapeutics, Inc. may not permit any person to consolidate with or merge into Cell Therapeutics, Inc. or convey, transfer, sell or lease such person’s properties and assets substantially as an entirety to Cell Therapeutics, Inc., unless each of the following requirements is met:

• Cell Therapeutics, Inc. is the surviving person or the person formed by the consolidation or into which Cell Therapeutics, Inc. is merged or the person to which its properties and assets are conveyed, transferred, sold or leased, is (1) a corporation, limited liability company, partnership or trust organized and existing under the laws of the United States, any State or the District of Columbia or (2) organized under the laws of a jurisdiction outside the U.S. and has common stock or American Depositary Shares representing such common stock traded on a national securities exchange in the U.S., including The Nasdaq Stock Market, Inc. and, in each case, if other than Cell Therapeutics, Inc., expressly assumes the due and punctual payment of the principal of, any premium, and interest (and additional interest under the registration rights agreement, if any) on the notes and the performance of our other covenants under the indenture;

• immediately after giving effect to that transaction, no event of default, and no event that, after notice or lapse of time or both, would become an event of default, shall have occurred and be continuing; and

• other conditions described in the indenture are met.

Upon any consolidation or merger or any transfer of all or substantially all of Cell Therapeutics, Inc.’s assets, the successor corporation formed by such consolidation or into which Cell Therapeutics, Inc. is merged or to which such transfer is made, shall succeed to, and be substituted for, and may exercise every right and power of, Cell Therapeutics, Inc. under the indenture with the same effect as if such successor corporation had been named in the indenture as Cell Therapeutics, Inc., and Cell Therapeutics, Inc. shall be released from the obligations under the notes and the indenture except with respect to any obligations that arise from, or are related to, such transaction.

Events of Default

The following are “events of default” under the indenture:

• we fail to pay principal of or any premium on any note when due;

• we fail to pay any interest on any note when due and that default continues for 30 days;

• we fail to give the notice that we are required to give if there is a change in control (as defined in the indenture);

• we fail to perform any other covenant in the indenture and that failure continues for 30 days after written notice to us by the trustee or the holders of at least $1,000,000 in aggregate principal amount of outstanding notes;

• we fail to pay when due the principal of any indebtedness for money borrowed by us or any of our significant subsidiaries, if any, in excess of $10 million if the indebtedness is not discharged and such failure continues for 30 days or more, or, if such indebtedness has been accelerated, such acceleration is not annulled, within 30 days after written notice to us by the trustee or the holders of at least $1,000,000 in aggregate principal amount of the outstanding notes;

• we fail to pay when due any amount due to preferred stock holders of the company or any subsidiary and that failure continues for 30 days, or the liquidation preference of such preferred stock has been accelerated and such acceleration is not annulled, within 30 days after written notice to us by the trustee or holders of at least $1,000,000 in aggregate principal amount of the notes;

• the company or a subsidiary redeems, purchases or otherwise acquires directly or indirectly any preferred stock in exchange for cash, cash equivalents or indebtedness with a maturity prior to that of these notes, except after payment of outstanding interest and any accrued interest on these notes; and

• certain events of bankruptcy, insolvency or reorganization with respect to Cell Therapeutics, Inc. and its significant subsidiaries specified in the indenture.

Subject to the provisions of the indenture relating to the trustee’s duties, if an event of default exists, the trustee will not be obligated to exercise any of its rights or powers under the indenture at the request or direction of any of the holders, unless they have offered to the trustee reasonable indemnity. Subject to such trustee indemnification provisions, the holders of a majority in aggregate principal amount of the outstanding notes have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee, provided that such direction does not conflict with any rule of law or with the indenture, and the trustee may take any other action the trustee deems proper which is not inconsistent with such direction.

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If an event of default, other than an event of default arising from certain events of bankruptcy, insolvency or reorganization with respect to Cell Therapeutics, Inc. specified in the indenture, occurs and is continuing, either the trustee or the each holder of at least $1,00,000 in principal amount of the outstanding notes may accelerate the maturity of all notes.

After acceleration, but before a judgment or decree based on acceleration, the holders of a majority in aggregate principal amount of outstanding notes may, under circumstances set forth in the indenture, rescind the acceleration if all events of default, other than the non-payment of principal of the notes which have become due solely because of the acceleration, have been cured or waived as provided in the indenture.

If an event of default arising from events of bankruptcy, insolvency or reorganization with respect to Cell Therapeutics, Inc. occurs and is continuing, then the principal of, and accrued interest (and liquidated damages, if any) on, all of the notes will automatically become immediately due and payable without any declaration or other act on the part of the holders of the notes or the trustee.

You do not have any right to institute any proceeding relating to the indenture, or to appoint a receiver or a trustee, or for any other remedy under the indenture, unless:

• you have given the trustee written notice of a continuing event of default;

• the registered holders of at least $1,000,000 of the aggregate principal amount of all outstanding notes have made a written request of the trustee to take action because of the default and have furnished reasonable indemnification to the trustee against the cost, liabilities and expenses of taking such action;

• the trustee shall not have taken action for 30 days after receiving such notice and offer of indemnification; or

• the trustee has not received any direction inconsistent with such written request from the holders of a majority of the aggregate principal amount of all outstanding notes during such 30-day period.

These limitations do not apply to a suit for the enforcement of payment of the principal of, or any premium or interest (and liquidated damages, if any) on, a note, or the repurchase price payable for a note on or after the due dates for such payments, or of the right to convert the note in accordance with the indenture.

We will furnish to the trustee annually a statement as to our performance of our obligations under the indenture and as to any default in performance.

Modification and Waiver

The indenture contains provisions permitting us and the trustee to enter into a supplemental indenture for certain limited purposes without the consent of the holders of the notes. With the consent of the holders of not less than a majority in aggregate principal amount of the notes at the time outstanding, we and the trustee are permitted to amend or supplement the indenture or any supplemental indenture or modify the rights of the holders, provided, that no such modification may, without the consent of each holder affected thereby:

• change the stated maturity of the principal or interest of any note;

• reduce the principal amount, any premium or interest on any note;

• reduce the amount payable on any note upon a redemption at our option;

• change the place or currency of payment on any note;

• impair the right to institute suit for the enforcement of any payment on any note;

• adversely affect the right of any holder of notes to convert its notes;

• modify the ranking provisions in a manner that is adverse to the holder of any notes;

• reduce the percentage of holders whose consent is needed to modify, amend or waive any provision in the indenture;

• modify the provisions dealing with modification and waiver of the indenture, except to increase any required percentage or to provide that certain other provisions of the indenture cannot be modified or waived without the consent of the holder of each outstanding note affected thereby; or

• amend or modify our obligation to make or consummate a repurchase offer upon a change in control after our obligation to make a change in control repurchase offer arises.

The holders of a majority in principal amount of the outstanding notes may waive our compliance with certain restrictive provisions of the indenture. The holders of a majority in principal amount of the outstanding notes may waive any past default, except a default in the payment of principal, any premium, interest or the repurchase price.

Notes are not considered outstanding if money for their payment or redemption has been deposited or set aside in trust for the holders.

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Registration Rights

In connection with the initial private placement of the notes, we entered into a registration rights agreement with each investor in the notes. In the registration rights agreement we agreed, for the benefit of the holders of the notes, the common stock and the shares of common stock issuable upon conversion of the notes, commonly referred to as the registrable securities, that we would, at our expense:

• use our best efforts to file with the SEC, as soon as practicable, but not later than 90 days, following the date the notes and common stock were originally issued, a shelf registration statement covering resales of the registrable securities;

• cause the shelf registration statement to be declared effective under the Securities Act on or prior to 180 days following the date the notes and common stock were originally issued, subject to our right to postpone having the shelf registration statement declared effective for an additional 60 days in limited circumstances; and

• use our best efforts to keep effective the shelf registration statement until the earlier of:

• all record holders of registrable securities are able to sell all registrable securities immediately without restriction pursuant to Rule 144(k) under the Securities Act or any successor rule thereto,

• all registrable securities registered under the shelf registration statement have been sold, or

• all registrable securities have ceased to be outstanding.

Notwithstanding any postponement of the effectiveness of the shelf registration statement, we are required to pay additional interest at a rate per annum of an additional one-half of one percent (0.50%) of the principal amount of the notes then outstanding if (i) the shelf registration statement is not filed with the SEC on or prior to 90 days following the date the notes and common stock were originally issued, (ii) the shelf registration statement is not declared effective by the SEC on or prior to 180 days following the date the notes and common stock were originally issued, (iii) the shelf registration statement ceases to be effective, other than due to suspension period (as discussed below) and we fail to file and have declared effective a post-effective amendment to make such shelf registration statement effective within 5 business days, (iv) the suspension periods (as discussed below) exceed 60 calendar days in any 12 month calendar period, or (v) we fail to timely comply with any of our obligations relating to sending questionnaires to holders upon request and filing registration statements of prospectus supplements, as appropriate with the SEC, provided that such failure is not solely due to a holder of the notes to deliver a completed and signed notice and questionnaire. Such additional interest shall be imposed from and including the day following the failure to comply with any of our obligations under clauses (i) through (v) above, to but excluding the day on which such failure is cured.

We will provide to each holder of registrable securities copies of the prospectus that is a part of the shelf registration statement, notify each holder when the shelf registration statement has become effective and take certain other actions required to permit public resales of the registrable securities.

Upon written notice to all the holders of notes, we are permitted to suspend the use of the prospectus that is part of the shelf registration statement in connection with sales of registrable securities during prescribed periods of time if we possess material non-public information the disclosure of which would have a material adverse effect on us. The periods during which we can suspend the use of the prospectus may not exceed a total of 30 calendar days in any 12 month calendar period and not exceed 10 consecutive calendar days in any 12 month period. Upon receipt of such notice, the holders of notes are required to cease disposing of securities under the prospectus and to keep the notice confidential.

A holder who elects to sell any registrable securities pursuant to the shelf registration statement is required to be named as a selling security holder in the related prospectus, may be required to deliver a prospectus to purchasers, may be subject to certain civil liability provisions under the Securities Act in connection with those sales and is bound by the provisions of the registration rights agreement that apply to a holder making such an election, including certain indemnification provisions.

We have filed this registration statement to meet our obligations under the registration rights agreements. We will mail a notice and questionnaire to obtain certain information regarding the holders for inclusion in this prospectus.

No holder of registrable securities will be entitled to be named as a selling security holder in the shelf registration statement as of the effective time, and no holder of registrable securities will be entitled to use the prospectus forming a part of the shelf registration statement for offers and resales of registrable securities at any time, unless such holder has returned a completed and signed notice and questionnaire to us by the deadline for response set forth in the notice and questionnaire. Holders of registrable securities will, however, have at least 10 calendar days from the date on which the notice and questionnaire is first received by them to return a completed and signed notice and questionnaire to us.

Beneficial owners of registrable securities who have not returned a notice and questionnaire by the questionnaire deadline described above may receive another notice and questionnaire from us upon request. When we receive a completed and signed notice and questionnaire prior to the effective time of the registration statement, we will include the registrable

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securities covered thereby in the shelf registration statement, subject to restrictions on the timing and number of supplements to the shelf registration statement provided in the registration rights agreement.

We agree in the registration rights agreement to cause the shares of common stock issuable upon conversion of the notes to be quoted on the Nasdaq National Market. However, if the common stock is not then quoted on the Nasdaq National Market, we will use our reasonable efforts to cause the shares of common stock issuable upon conversion of the notes to be quoted or listed on whichever market or exchange the common stock is then quoted or listed, if any, on or prior to the effectiveness of the shelf registration statement.

This summary of certain provisions of the registration rights agreement is not complete and is subject to, and qualified in its entirety by reference to, all the provisions of the registration rights agreement.

We will give notice to holders of the notes by mail to the addresses of the holders as they appear in the security register. Notices will be deemed to have been given on the date of mailing.

Replacement of Notes

We will replace, at the holders’ expense, notes that become mutilated, destroyed, stolen or lost upon delivery to the trustee of the mutilated notes or evidence of the loss, theft or destruction thereof satisfactory to us and the trustee. In the case of a lost, stolen or destroyed note, indemnity satisfactory to the trustee and us may be required before a replacement note will be issued. Any issuance of a replacement note shall be at the expense of the holder.

Governing Law

The indenture, the notes and the registration rights agreement will be governed by and construed in accordance with the laws of the State of New York, United States of America.

The Trustee

The trustee for the holders of notes issued under the indenture will be U.S. Bank National Association. If an event of default occurs, and is continuing, the trustee will be required to use the degree of care of a prudent person in the conduct of his own affairs in the exercise of its powers. Subject to these provisions, the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request of any holders of notes, unless they have offered the trustee reasonable security or indemnity.

Absence of Public Market

There is no existing market for the notes and there can be no assurance as to the liquidity of any markets that may develop for the notes, the ability of holders to sell their notes or at what price holders of the notes will be able to sell their notes. Future trading prices of the notes will depend upon many factors including, among other things, prevailing interest rates, our operating results, the price of our common stock and the market for similar securities. The notes are eligible for trading in The PORTAL Market. We do not intend to apply for listing of the notes on any securities exchange. See the section entitled “Plan of Distribution” for more information.

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SELLING SECURITYHOLDERS

All of the notes and shares of common stock registered for sale pursuant to this prospectus are owned by the selling securityholders. All of the notes and shares offered hereby were acquired by the selling securityholders in a private placement in December 2007. Except where otherwise noted, no selling securityholder has a material relationship with the Company.

The following table and related footnotes contains information as of March 27, 2008, with respect to the selling securityholders and principal amount of notes and the number of shares of commons tock beneficially owned by each selling securityholder that may be offered using this prospectus.

Percentage of beneficial ownership is based on shares of our common stock outstanding as of March 25, 2008. The selling shareholders may offer the shares for sale from time to time in whole or in part. Except where otherwise noted, the selling shareholders named in the following table has, to our knowledge, sole voting and investment power with respect to the shares beneficially owned by them.

Selling Securityholder	Principal Amount at Maturity of Notes Beneficially Owned That May be Sold		Percentage of Notes Outstanding (1)		Number of Shares of Common Stock That May be Sold (2)	Shares Beneficially Owned Prior to this Offering (3)(4)	Shares Beneficially Owned After Completion of this Offering (3)	Percentage of Common Stock Outstanding After Completion of this Offering (3)
Tribeca Convertibles LP	$	2,000,000	8.6	%	666,666	666,666	—	—
Kamunting Street Master Fund, Ltd.	$	2,000,000	8.6	%	666,666	666,666	—	—
Deltec Recovery Fund, LP	$	1,500,000	6.5	%	500,000	500,000	—	—
Oaktree Capital Management, L.P.(5)(6)	$	4,000,000	17.2	%
Bruce Fund	$	5,250,000	22.58	%	1,749,998	1,749,998	—	—
Leestma Family Foundation	$	140,000	*		46,667	46,667	—	—
JM Marsilje Trust	$	70,000	*		23,333	23,333	—	—
Leestma Family Trust	$	70,000	*		23,333	23,333	—	—
Thomas O’Malley IRA	$	175,000	*		58,333	58,333	—	—
Professional Life	$	410,000	1.8	%	136,667	136,667	—	—
Little Flower Fund	$	35,000	*		11,667	11,667	—	—
Alex DeBartolo IRA	$	105,000	*		35,000	35,000	—	—
Bruce Foundation	$	70,000	*		23,333	23,333	—	—
Louise Leestma Trust	$	140,000	*		46,667	46,667	—	—
Roger Leestma Trust	$	15,000	*		5,000	5,000	—	—
Robert Bruce	$	350,000	1.5	%	116,667	116,667	—	—
Nancy Bruce	$	140,000	*		46,667	46,667	—	—
Susan Bruce	$	70,000	*		23,333	23,333	—	—
Elizabeth Bruce	$	70,000	*		23,333	23,333	—	—
Carrie Bruce	$	70,000	*		23,333	23,333	—	—
Wolverine Convertible Arbitrage Fund Trading Limited	$	4,725,000	20.3	%	861,702	2,505,947	1,644,245	1.7	%
GPC LX, LLC	$	525,000	2.3	%	95,745	245,221	149,476	*
Any other holder of notes or future transferee, pledgee, donee, or successor of any holder(7)(8)	$	1,250,000	5.4	%	1,586,879	1,586,879	—	—

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* Less than 1%

(1) $23,250,000 million aggregate principal of Notes outstanding.

(2) Assumes issuance of all shares covered by this prospectus, including those shares issuable upon conversion of the selling securityholder’s notes.

(3) Does not include any shares of common stock issuable upon the conversion of our outstanding convertible debt or other convertible securities owned by a holder, other than the 5.75% Convertible Senior Notes being registered here.

(4) Calculated based on Rule 13d-3(d)(1)(i) of the Exchange Act using 94,634,431 shares of common stock outstanding as of March 25, 2008. We did not assume the issuance of any other shares issuable upon exercise of outstanding warrants or options or conversion of any outstanding convertible notes.

(5) Acts as agent for the following selling securityholders with ownership as indicated: OCM High Income Convertible Limited Partnership holds $94,000 aggregate principal amount of Notes convertible into 31,333 shares of common stock; High Income Convertible Fund II Limited Partnership holds $217,000 aggregate principal amount of Notes convertible into 72,333 shares of common stock; OCM Global Securities Fund - High Income holds $59,000 aggregate principal amount of Notes convertible into 19,667 shares of common stock; San Diego County Retirement Association - High Income Convertible holds $35,000 aggregate principal amount of Notes convertible into 11,667 shares of common stock; Microsoft Capital Group, LP (High Income) holds $241,000 aggregate principal amount of Notes convertible into 80,333 shares of common stock; Ace Tempest Reinsurance Ltd. - High Income holds $260,000 aggregate principal amount of Notes convertible into 86,667 shares of common stock; Tripar Partnership - High Income holds $260,000 aggregate principal amount of Notes convertible into 86,667 shares of common stock; General Motors Foundation Inc. holds $60,000 aggregate principal amount of Notes convertible into 20,000 shares of common stock; Richard King Mellon Foundation holds $185,000 aggregate principal amount of Notes convertible into 61,667 shares of common stock; GMAM Investment Funds Trust II holds $864,000 aggregate principal amount of Notes convertible into 288,000 shares of common stock; The Long Term Investment Trust (AT&T) holds $847,000 aggregate principal amount of Notes convertible into 282,333 shares of common stock; Virginia Retirement System - High Income holds $416,000 aggregate principal amount of Notes convertible into 138,667 shares of common stock; and Arch Reinsurance holds $462,000 aggregate principal amount of Notes convertible into 154,000 shares of common stock. Oaktree Capital Management, L.P. is the investment manager for each of these entities. It does not own any equity interest in these selling securityholders, but has voting and dispositive power over the aggregate principal amount of Notes for each.

(6) Oaktree Capital Management, L.P. is the investment manager of each selling securityholder listed in footnote (6) above. Oaktree Capital Management, L.P. is the majority owner of OCM Investments, LLC, a broker-dealer.

(7) Information about other selling securityholders will be set forth in prospectus supplements, if required.

(8) Assumes that any other holder of notes, or any future transferees, pledgees, donees or successors of or from any such other holders of notes, do not beneficially own any common stock other than the common stock issuable upon conversion of the notes at the initial conversion rate or the common stock issued in connection with the notes.

The selling securityholders provided us with information with respect to their share ownership. Because the selling securityholders may sell all, part or none of its notes and shares, we are unable to estimate the amount of notes or number of shares that will be held by the selling securityholders upon resale of the notes and shares of common stock being registered hereby. We have, therefore, assumed for the purposes of the registration statement related to this prospectus that the selling securityholders will sell all of their notes and shares. See “Plan of Distribution.”

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PLAN OF DISTRIBUTION

The selling securityholders and any of its pledgees, assignees and successors-in-interest may, from time to time, sell any or all of the shares of common stock on any stock exchange, market or trading facility on which the shares are traded or in private transactions. These sales may be at fixed or negotiated prices. The selling securityholders may use any one or more of the following methods when selling shares:

• ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;

• block trades in which the broker-dealer will attempt to sell the shares as agent but may position and resell a portion of the block as principal to facilitate the transaction;

• purchases by a broker-dealer as principal and resale by the broker-dealer for its account;

• an exchange distribution in accordance with the rules of the applicable exchange;

• privately negotiated transactions;

• settlement of short sales;

• broker-dealers may agree with the selling stockholder to sell a specified number of such shares at a stipulated price per share;

• a combination of any such methods of sale;

• through the writing or settlement of options or other hedging transactions, whether through an options exchange or otherwise; or

• any other method permitted pursuant to applicable law.

The selling securityholders may also sell shares under Rule 144 under the Securities Act, if available, rather than under this prospectus.

Broker-dealers engaged by the selling securityholders may arrange for other brokers-dealers to participate in sales. Broker-dealers may receive commissions or discounts from the selling securityholders (or, if any broker-dealer acts as agent for the purchaser of shares, from the purchaser) in amounts to be negotiated. The selling securityholders do not expect these commissions and discounts relating to its sales of shares to exceed what is customary in the types of transactions involved.

In connection with the sale of our common stock or interests therein, the selling securityholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the common stock in the course of hedging the positions they assume. The selling securityholders may also sell shares of our common stock short and deliver these securities to close out its short positions, or loan or pledge the common stock to broker-dealers that in turn may sell these securities. The selling securityholders may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of shares offered by this prospectus, which shares such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

The selling securityholders and any broker-dealers or agents that are involved in selling the shares may be deemed to be “underwriters” within the meaning of the Securities Act in connection with such sales. In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. The selling securityholders have informed us that it does not have any agreement or understanding, directly or indirectly, with any person to distribute the common stock.

Because the selling securityholders may be deemed to be “underwriters” within the meaning of the Securities Act, they will be subject to the prospectus delivery requirements of the Securities Act. In addition, any securities covered by this prospectus which qualify for sale pursuant to Rule 144 under the Securities Act may be sold under Rule 144 rather than under this prospectus. The selling securityholders have advised us that it has not entered into any agreements, understandings or arrangements with any underwriter or broker-dealer regarding the sale of the resale shares. There is no underwriter or coordinating broker acting in connection with the proposed sale of the resale shares by the selling securityholders.

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The shares will be sold only through registered or licensed brokers or dealers if required under applicable state securities laws. In addition, in certain states, the shares may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

Under applicable rules and regulations under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), any person engaged in the distribution of the resale shares may not simultaneously engage in market making activities with respect to our common stock for a period of two business days prior to the commencement of the distribution. In addition, the selling securityholders will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including Regulation M, which may limit the timing of purchases and sales of shares of our common stock by the selling securityholders or any other person. We will make copies of this prospectus available to the selling securityholders and have informed the selling shareholders of the need to deliver a copy of this prospectus to each purchaser at or prior to the time of the sale.

We will not receive any proceeds from the sale of the shares by the selling securityholders.

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LEGAL MATTERS

The validity of the securities offered hereby and certain other legal matters in connection therewith will be passed upon for us by Heller Ehrman LLP, Seattle, Washington.

EXPERTS

Stonefield Josephson, Inc., an independent registered public accounting firm, has audited our consolidated financial statements and consolidated financial statement schedule at December 31, 2007, and for each of the three years in the period ended December 31, 2007, included in our Annual Report on Form 10-K for the year ended December 31, 2007, as set forth in its report, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Such consolidated financial statements and consolidated financial statement schedule are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

We are subject to the information requirements of the Securities Exchange Act of 1934 (hereinafter the “Exchange Act”). In accordance with the Exchange Act, we file reports, proxy statements and other information with the SEC. Such reports, proxy statements and other information filed by us are available free of charge on our web site, http://www.cticseattle.com, and may be inspected and copied at the public reference facilities maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the public reference facilities by calling the SEC at 1-800-SEC-0330. The SEC maintains an Internet site at http://www.sec.gov that contains reports, proxy and information statements and other information regarding registrants that file electronically with the SEC.

Our common stock is listed on the Nasdaq Global Market and such reports, proxy statements and other information concerning us may be inspected at the offices of The Nasdaq Stock Market, 1735 K Street, N.W., Washington, D.C. 20006.

DOCUMENTS INCORPORATED BY REFERENCE

SEC rules allow us to “incorporate by reference” into this prospectus the information we file with the SEC. This means that we can disclose important information by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus. Information that we file later with the Commission will automatically update and supersede this information. We incorporate by reference the documents listed below:

• our Annual Report on Form 10-K for the fiscal year ended December 31, 2007, as amended;

• our definitive Proxy Statements on Schedule 14A, dated and filed with the SEC on August 28, 2007 for our 2007 Annual Meeting of Shareholders and on December 21, 2007 for our Special Meeting of the Shareholders;

• our Current Reports on Form 8-K, and Amended Current Reports filed on Form 8-K/A, filed on January 3, 2008, January 14, 2008, January 18, 2008, January 29, 2008, February 5, 2008, February 19, 2008, March 5, 2008, March 11, 2008 and March 21, 2008; and

• The description of our capital stock contained in our Registration Statements on Form 10 filed with the SEC on June 27, 1996 and June 28, 1996, including any amendment or reports filed for the purpose of updating that description.

In addition, we also incorporate by reference into this prospectus additional information that we may subsequently file with the Securities and Exchange Commission under Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the termination of the offering. These documents include Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as well as proxy statements.

Notwithstanding the foregoing, unless specifically stated to the contrary, none of the information that we disclose under Items 2.02 or 7.01 of any Current Report on Form 8-K that we may from time to time furnish to the Securities and Exchange Commission will be incorporated by reference into, or otherwise included in, this prospectus.

We are subject to the information and reporting requirements of the Exchange Act, and file periodic reports, proxy statements and we make available to our stockholders annual reports containing audited financial information for each year and quarterly reports for the first three quarters of each fiscal year containing unaudited interim financial information.

We will provide without charge to each person, including any beneficial owner of CTI common stock, to whom this prospectus is delivered, upon written or oral request, a copy of any and all of the documents that have been incorporated by reference in the prospectus but not delivered with this prospectus (without exhibits, unless the exhibits are specifically incorporated by reference but not delivered with this prospectus). Requests should be directed to:

Louis A. Bianco

Executive Vice President, Finance and Administration

Cell Therapeutics, Inc.

501 Elliott Avenue West, Suite 400

Seattle, Washington 98119

(206) 282-7100

You should rely only on the information contained in this prospectus. We have not authorized any person to provide you with information different from that contained in this prospectus. This prospectus may be used only where it is legal to sell the common stock of Cell Therapeutics, Inc. The information contained in this prospectus is accurate only as of the date of this prospectus, regardless of the date of delivery of this prospectus or of any sale of the common stock of Cell Therapeutics, Inc.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution

The following table sets forth an estimate of the fees and expenses payable by the registrant in connection with the registration of the securities offered hereby. All of such fees expenses, except for the Registration Fee, are estimated:

Securities and Exchange Commission registration fee	$	945.68
Accounting fees and expenses		1,000
Legal fees and expenses		15,000
Miscellaneous		5,000
Total	$	21,945.68

All expenses in connection with the issuance and distribution of the securities being offered shall be borne by the registrant, other than underwriting discounts and selling commissions, if any.

Item 15. Indemnification of Directors and Officers

Sections 23B.08.500 through 23B.08.600 of the Washington Business Corporation Act (the “WBCA”) authorize a court to award, or a corporation’s board of directors to grant, indemnification to directors and officers on terms sufficiently broad to permit indemnification under certain circumstances for liabilities arising under the Securities Act of 1933. Article IX of the Registrant’s Restated Bylaws provides for indemnification of the Registrant’s directors, officers, employees and agents to the maximum extent permitted by Washington law. The directors and officers of the Registrant also may be indemnified against liability they may incur for serving in such capacity pursuant to a liability insurance policy maintained by the Company for such purpose.

Section 23B.08.320 of the WBCA authorizes a corporation to limit a director’s liability to the corporation or its shareholders for monetary damages for acts or omissions as a director, except in certain circumstances involving intentional misconduct, knowing violations of law or illegal corporate losses or distributions, or any transaction from which the director personally receives a benefit in money, property or services to which the director is not legally entitled. Article VI of the Registrant’s Restated Articles of Incorporation contains provisions implementing, to the fullest extent permitted by Washington law, such limitations on a director’s liability to the Registrant and its shareholders.

The Registrant has entered into an indemnification agreement with each of its executive officers and directors in which the Registrant agrees to hold harmless and indemnify the officer or director to the fullest extent permitted by Washington law. The Registrant agrees to hold harmless and indemnify the officer or director against any and all losses, claims, damages, liabilities or expenses incurred in connection with any actual, pending or threatened action, suit, claim or proceeding, whether civil, criminal, administrative or investigative and whether formal or informal, in which the officer or director is, was or becomes involved by reason of the fact that the officer or director is or was a director, officer, employee, trustee or agent of the Registrant or any related company, partnership or enterprise, including service with respect to an employee benefit plan, whether the basis of such proceeding is alleged action (or inaction) by the officer or director in an official capacity and any action, suit, claim or proceeding instructed by or at the direction of the officer or director unless such action, suit, claim or proceeding is or was authorized by the Registrant’s Board of Directors. No indemnity pursuant to the indemnification agreements shall be provided by the Registrant on account of any suit in which a final, unappealable judgment is rendered against the officer or director for an accounting of profits made from the purchase or sale by the officer or director of securities of the Registrant in violation of the provisions of Section 16(b) of the Securities Exchange Act of 1934, and amendments thereto, or for damages that have been paid directly to the officer or director by an insurance carrier under a policy of directors’ and officers’ liability insurance maintained by the Registrant.

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Item 16. Exhibits and Financial Statement Schedules

(a) Exhibits

Exhibit Number	Description
3.1(a)	Registrant’s Amended and Restated Articles of Incorporation (1)
3.1(b)	Registrant’s Amended and Restated Bylaws. (2)
4.1	Indenture, dated December 12, 2007 between Cell Therapeutics, Inc. and U.S. Bank National Association, as trustee (3)
4.2	Form of Note (included in Exhibit 4.1)
4.3	Form of Registration Rights Agreement, dated as of December 12, 2007, between Cell Therapeutics, Inc. and the certain other party thereto. (3)
4.4	Specimen Common Stock Certificate (4)
5.1	Opinion of Heller Ehrman LLP
12.1	Computation of Ratio of Earnings to Fixed Charges.
23.1	Consent of Stonefield Josephson, Inc., Independent Registered Public Accounting Firm
23.2	Consent of Heller Ehrman LLP (included in Exhibit 5.1)
24.1	Power of Attorney (included on signature page of the Registration Statement hereto)
25.1	Form T-1 Statement of Eligibility of Trustee for Indenture under the Trust Indenture Act of 1939.

(1) Incorporated by reference to exhibits to the Registrant’s Current Report on Form 8-K filed January 29, 2008.

(2) Incorporated by reference to appendix H to the Registrant’s Registration Statement on Form S-4 (No. 333-106906).

(3) Incorporated by reference to exhibits to the Registrant’s Current Report on Form 8-K filed December 13, 2007.

(4) Incorporated by reference to exhibits to the Registrant’s Registration Statement on Form 10, as amended.

Item 17. Undertakings

(a) The undersigned registrant hereby undertakes:

1. To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement.

2. That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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3. To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

4. That, for the purposes of determining liability under the Securities Act of 1933 to any purchaser:

(i) If the registrant is relying on Rule 430B:

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

5. That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities: The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant named below certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3, and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Seattle, state of Washington, on this 26^th day of March, 2008.

CELL THERAPEUTICS, INC.
By:	/s/ James A. Bianco
	James A. Bianco, M.D.
	President and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that the undersigned officers and directors of Cell Therapeutics, Inc., a Washington corporation, do hereby constitute and appoint James A. Bianco and Louis A. Bianco and each of them individually, the lawful attorneys-in-fact and agents, each with full power of substitution or re-substitution, with full power and authority to do any and all acts and things and to execute any and all instruments which said attorneys-in-fact and agents, or either one of them, determine may be necessary or advisable or required to enable said corporation to comply with the Securities Act of 1933, as amended, and any rules or regulation or requirements of the Securities and Exchange Commission in connection with this Registration Statement. Without limiting the generality of the foregoing power and authority, the powers granted include the power and authority to sign the names of the undersigned officers and directors in the capacities indicated below to this Registration Statement, to any and all amendments, both pre-effective and post-effective, and supplements to this Registration Statement and to any and all instruments or documents filed as part of or in conjunction with this Registration Statement or amendments or supplements thereto, and each of the undersigned hereby ratifies and confirms all that said attorneys-in-fact and agents, or either one of them, shall do or cause to be done by virtue hereof. This Power of Attorney may be signed in several counterparts.

IN WITNESS WHEREOF, each of the undersigned has executed this Power of Attorney as of the date indicated.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ Philip M. Nudelman Phillip M. Nudelman, Ph.D.	Chairman of the Board	March 25, 2008
/s/ James A. Bianco James A. Bianco, M.D.	President, Chief Executive Officer and Director (Principal Executive Officer)	March 26, 2008
/s/ Louis A. Bianco Louis A. Bianco	Executive Vice President, Finance and Administration (Principal Financial Officer and Principal Accounting Officer)	March 26, 2008
/s/ John H. Bauer John H. Bauer	Director	March 25, 2008
/s/ Vartan Gregorian Vartan Gregorian, Ph.D.	Director	March 25, 2008
/s/ Richard L. Love Richard L. Love	Director	March 26, 2008
/s/ Mary O. Mundinger Mary O. Mundinger, Dr. PH	Director	March 26, 2008
/s/ Jack W. Singer Jack W. Singer, M.D.	Director	March 26, 2008
/s/ Frederick W. Telling Frederick W. Telling, Ph.D.	Director	March 26, 2008

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EXHIBIT INDEX

Exhibit Number	Description
3.1(a)	Registrant’s Amended and Restated Articles of Incorporation (1)
3.1(b)	Registrant’s Amended and Restated Bylaws. (2)
4.1	Indenture, dated December 12, 2007 between Cell Therapeutics, Inc. and U.S. Bank National Association, as trustee (3)
4.2	Form of Note (included in Exhibit 4.1)
4.3	Form of Registration Rights Agreement, dated as of December 12, 2007, between Cell Therapeutics, Inc. and the certain other party thereto. (3)
4.4	Specimen Common Stock Certificate (4)
5.1	Opinion of Heller Ehrman LLP
12.1	Computation of Ratio of Earnings to Fixed Charges.
23.1	Consent of Stonefield Josephson, Inc., Independent Registered Public Accounting Firm
23.2	Consent of Heller Ehrman LLP (included in Exhibit 5.1)
24.1	Power of Attorney (included on signature page of the Registration Statement hereto)
25.1	Form T-1 Statement of Eligibility of Trustee for Indenture under the Trust Indenture Act of 1939.

(1) Incorporated by reference to exhibits to the Registrant’s Current Report on Form 8-K filed January 29, 2008.

(2) Incorporated by reference to appendix H to the Registrant’s Registration Statement on Form S-4 (No. 333-106906).

(3) Incorporated by reference to exhibits to the Registrant’s Current Report on Form 8-K filed December 13, 2007.

(4) Incorporated by reference to exhibits to the Registrant’s Registration Statement on Form 10, as amended.