8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

Current Report Pursuant to Section 13 or 15(d) of
The Securities Exchange Act of 1934

May 11, 2009

Date of Report (Date of earliest event reported)

OSI PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

Delaware	0-15190	13-3159796
(State or other jurisdiction of incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

41 Pinelawn Road
Melville, NY 11747

(Address of principal executive offices)

(631) 962-2000

(Registrant’s telephone number, including area code)

N/A

(Former name or former address,

if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a- 12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01. Other Events.

     On May 11, 2009, OSI Pharmaceuticals, Inc (“OSI”) provided an update on the progress of PSN821 and PSN602, two early clinical programs from its diabetes and obesity research and development operations. The data will be submitted for presentation at future scientific meetings. A copy of OSI’s press release, dated May 11, 2009, is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

     On May 14, 2009, OSI announced detailed results from the Phase III study of Tarceva® (erlotinib) as a single agent, first-line maintenance therapy for patients with advanced non-small cell lung cancer who did not progress following first-line treatment with platinum-based chemotherapy, referred to as the SATURN study. Data are being released co-incident with the publication of on-line abstracts by the American Society of Clinical Oncology (“ASCO”) in advance of their Annual Meeting in Orlando on May 29-June 2, 2009. A copy of OSI’s press release, dated May 14, 2009, is attached hereto as Exhibit 99.2 and is incorporated herein by reference.

     On May 15, 2009, OSI announced preliminary data from two phase I dose escalation studies of oral OSI-906, a small molecule insulin-like growth factor-1 receptor tyrosine kinase inhibitor, in patients with advanced solid tumors. The data will be presented at the ASCO Annual Meeting on May 30, 2009. A copy of OSI’s press release, dated May 15, 2009, is attached hereto as Exhibit 99.3 and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits.

Exhibit No.	Description
99.1	Press release dated May 11, 2009.
99.2	Press release dated May 14, 2009.
99.3	Press release dated May 15, 2009.

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SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: May 19, 2009	OSI PHARMACEUTICALS, INC.
	By:	/s/ Barbara A. Wood
		Barbara A. Wood
		Senior Vice President, General Counsel and Secretary

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EXHIBIT INDEX

Exhibit No.	Description
99.1	Press release dated May 11, 2009.
99.2	Press release dated May 14, 2009.
99.3	Press release dated May 15, 2009.

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EX-99.1

Exhibit 99.1

NEWS RELEASE

Contacts:
OSI Pharmaceuticals, Inc.	Burns McClellan, Inc. (representing OSI)
Kathy Galante (investors/media)	Justin Jackson/Kathy Nugent (media)
Senior Director	(212) 213-0006
Kim Wittig (media)
Director
631-962-2000

OSI PHARMACEUTICALS PROVIDES UPDATE ON DIABETES AND
OBESITY CLINICAL PROGRAMS

MELVILLE, NEW YORK – May 11, 2009 — OSI Pharmaceuticals, Inc. (NASDAQ: OSIP) provided an update today on the progress of two early clinical programs from its diabetes and obesity R&D operations. Phase I clinical trial data on both PSN821 and PSN602 showed positive evidence of clinical activity, and both candidates are now progressing to the next stage of clinical development. PSN821 completed a single dose Phase I trial in healthy volunteers and diabetes patients, where evidence of glucose lowering was seen in response to a standard nutrient challenge. PSN602 completed a Phase I trial, where indications of activity in the form of significant reductions in food intake in standardized meal intake assessments were seen after 14 days of dosing in overweight/obese subjects. PSN821, an oral GPR119 agonist being developed for the treatment of type 2 diabetes and PSN602, an oral dual monoamine reuptake inhibitor and 5-HT_1A agonist being developed for the treatment of obesity, were discovered by OSI’s diabetes and obesity R&D team and are wholly owned by OSI. Full data from the PSN602 Phase I trial will be presented at a scientific meeting in the second half of 2009.

“We are pleased with the progress we have made in the first-in-human studies of PSN821 and PSN602,” stated Anker Lundemose, M.D., Ph.D., President of (OSI) Prosidion. “In keeping with our view that we should focus on establishing differentiation early in development programs, the follow-on studies for both PSN821 and PSN602 will include active comparator arms.”

PSN821 has progressed to a 14-day Phase I trial which may allow a preliminary assessment of impacts on gastric emptying and glucose data in addition to safety. Presuming continued success in this program, OSI will initiate a follow-on 28-day dosing Phase IIa study or a 3-month dosing Phase IIb study in 2010. The Phase II study will include sitagliptin as a comparator. PSN602 is now progressing with a 28-day dosing Phase IIa study, which includes sibutramine as a comparator.

PSN821-101: Phase I Data

In the double-blind, placebo-controlled, ascending single dose first-in-human study, PSN821 was generally well tolerated at doses up to 3000mg in healthy volunteers and 1000mg (the top dose tested) in patients with type 2 diabetes, with no clinically important adverse effects on laboratory tests, 12-lead ECGs or vital signs. Pharmacokinetics showed a profile consistent with once or twice daily dosing. In patients with type 2 diabetes, PSN821 showed substantial and statistically significant reductions in glucose responses to a standard nutrient challenge of approximately 30% at 250mg and 500mg. The data from this study was supportive of progression of PSN821 into a 14-day dosing ascending multiple dose study in healthy subjects and patients with type 2 diabetes and will be submitted for presentation at a scientific meeting together with the data from the multiple ascending dose study.

PSN602-101: Phase I Data

In the double-blind, placebo-controlled, ascending single and multiple dose first-in-human study, PSN602 was generally well tolerated at doses up to 20mg daily for 14 days. At 30mg daily for 14 days, the incidence of adverse events increased and one subject experienced syncope. There were no clinically important adverse effects on laboratory tests, 12-lead ECGs or vital signs apart from post-dose postural tachycardia. Pharmacokinetics showed a profile consistent with once daily dosing. In multiple dosing over 14 days in overweight/obese subjects, PSN602 showed substantial and statistically significant reductions from baseline in test meal intake of 36% and 25% at 20mg and 30mg respectively, comparing favourably with literature values for sibutramine of 15-25%. The data from this study is supportive of progression of PSN602 into a 28-day dosing clinical study, at a top dose of 20mg daily, with weight loss as the primary endpoint and sibutramine as a comparator, and will be presented at a scientific meeting.

About OSI Pharmaceuticals

OSI Pharmaceuticals is committed to “shaping medicine and changing lives” by discovering, developing and commercializing high-quality, novel and differentiated personalized medicines designed to extend life and improve the quality of life for patients with cancer and diabetes/obesity.

This news release contains forward-looking statements. These statements are subject to known and unknown risks and uncertainties that may cause actual future experience and results to differ materially from the statements made. Factors that might cause such a difference include, among others, OSI’s and its collaborators’ abilities to effectively market and sell Tarceva and to expand the approved indications for Tarceva, OSI’s ability to protect its intellectual property rights, safety concerns regarding Tarceva, competition to Tarceva and OSI’s drug candidates from other biotechnology and pharmaceutical companies, the completion of clinical trials, the effects of FDA and other governmental regulation, including pricing controls, OSI’s ability to successfully develop and commercialize drug candidates, and other factors described in OSI Pharmaceuticals’ filings with the Securities and Exchange Commission.

EX-99.2

Exhibit 99.2

NEWS RELEASE

Contacts:
OSI Pharmaceuticals, Inc.	Burns McClellan, Inc. (representing OSI)
Kathy Galante (investors/media)	Justin Jackson/Kathy Nugent (media)
Senior Director	(212) 213-0006
631-962-2043
Kim Wittig (media)
Director
631-962-2135

DATA FROM THE PHASE III SATURN STUDY SHOW TARCEVA
IMPROVED PROGRESSION-FREE SURVIVAL WHEN USED AS A FIRST-
LINE MAINTENANCE THERAPY FOR ADVANCED NON-SMALL CELL
LUNG CANCER

— Data Showed Tarceva Improved PFS in Patients with Both Non-Squamous Cell
Carcinoma and Squamous Cell Carcinoma —

— Patients with an EGFR Mutation Achieved a 10 Fold Increase in the Time Patients Live
Without Their Disease Worsening –

— Biomarker Data Suggest K-ras Mutation Status is not a Predictor of Efficacy in NSCLC
Patients Treated with Tarceva —

MELVILLE, NEW YORK – May 14, 2009 — OSI Pharmaceuticals, Inc. (NASDAQ: OSIP) announced detailed results from the Phase III SATURN study of Tarceva^® (erlotinib) as a single agent, first-line maintenance therapy for patients with advanced non-small cell lung cancer (NSCLC) who did not progress following first-line treatment with platinum-based chemotherapy. The study met both of its co-primary endpoints by demonstrating a statistically significant 41% improvement in the time patients live without their disease worsening (as measured by progression free survival, or PFS) compared with placebo (Hazard Ratio = 0.71, p-value <0.00001; a hazard ratio of less than one indicates a decreased risk of disease progression and a p-value of less than 0.03 indicates statistical significance) and a 45% increase in the time patients live without their disease worsening compared with placebo in the sub-set of patients who were determined to have tumors expressing the EGFR gene by Immunohistochemistry (IHC) (Hazard Ratio for PFS = 0.69, p-value <0.0001). The study confirmed findings from prior studies in later stage NSCLC patients that Tarceva demonstrated benefit across a broad spectrum of NSCLC patients. Importantly, the study demonstrated a PFS benefit for Tarceva maintenance therapy in both squamous cell carcinoma patients (HR=0.76, p-value=0.0148, n=359); and non-squamous patients (HR=0.68, p-value < 0.0001, n=525).

“The results of the SATURN study offer a clinically meaningful benefit for patients with advanced lung cancer,” said Professor Federico Cappuzzo, principal investigator on the SATURN study from the Istituto Clinico Humanitas IRCCS, Milan, Italy. “If we can offer patients a once-daily, oral therapy with a favorable safety profile right after chemotherapy to extend the time they live without their disease progressing, this is an important step forward in the treatment of lung cancer.”

Pre-planned biomarker analyses of tissue samples collected as part of the SATURN protocol provided important information on the potential role of EGFR mutations and K-ras mutations in predicting possible outcomes of Tarceva therapy in NSCLC patients. The subgroup analysis of patients whose tumors possessed an activating EGFR mutation and were eligible for analysis (n=49) demonstrated a statistically significant ten-fold increase in the time patients live without their disease worsening (as measured by PFS) for patients treated with Tarceva compared with placebo. The hazard ratio was 0.10 (p-value <0.0001). In the sub-population of patients tested for their EGFR mutation or wild-type status, a statistically significant PFS benefit of Tarceva therapy was also evident in patients with wild-type EGFR status after excluding those patients whose tumors had an activating EGFR mutation (HR=0.78, p-value < 0.0185, n=388).

In addition, the sub-group analysis of patients whose tumors possessed a K-ras mutation and were eligible for analysis (n=90) suggested a similar treatment benefit in terms of PFS to that seen in the overall population (HR=0.77, p-value=0.679).

The EGFR IHC status of the tumor was not predictive of outcome for Tarceva therapy in the study as demonstrated by HR of 0.69 in EGFR IHC positive (n=618) and HR of 0.77 in EGFR IHC negative (n=121) patients.

“The biomarker analyses in the SATURN study have shed an important light on the appropriate use of EGFR and K-ras mutation status biomarkers in Tarceva therapy. The data suggest that, while NSCLC patients with wild-type EGFR clearly benefit from Tarceva therapy, those whose tumors contain an EGFR mutation derive pronounced benefit and that those patients whose tumors contain a K-ras mutation should not be excluded from treatment with Tarceva,” stated Colin Goddard, Ph.D., Chief Executive Officer of OSI Pharmaceuticals. “Presuming successful regulatory approval, we believe Tarceva will be the therapy of choice for NSCLC patients in the maintenance setting whose tumors possess an EGFR mutation, are of squamous cell histology, or are chemo ineligible while continuing to offer a non-chemotherapy choice for all NSCLC patients in this setting.”

Twenty-five percent of patients treated with Tarceva had not seen their disease progress after six months compared with 15% of patients treated with placebo. Measurements of median PFS in the overall population in the study were impacted by an unusual step-wise data distribution in the Kaplan-Meier analysis (12.3 weeks for the Tarceva arm versus 11.1 weeks for the placebo arm) which is not representative of the robust overall PFS benefit as evident by the Hazard Ratio of 0.71 and an associated p-value of <0.00001.

Overall survival data (a secondary end-point in the study) is immature and is not expected to be available until later in the year. There were no new safety signals seen in the study and using Tarceva maintenance therapy immediately following first-line chemotherapy did not appear to exacerbate any residual chemotherapy related side-effects. Fifty-five percent of patients in the Tarceva arm and 64% of patients on placebo received subsequent therapy after progressing.

SATURN Safety Data

There were no new or unexpected safety signals observed in the SATURN study. Adverse events were consistent with those observed in previous Tarceva studies in NSCLC, and included rash (49.2% with Tarceva versus 5.8% with placebo) and diarrhea (20.3% with Tarceva versus 4.5% with placebo). Dose reductions were necessary in 11% of the patients treated with Tarceva versus 1% of those treated with placebo. Discontinuations due to adverse events were necessary for 4.6% of the patients in the Tarceva arm versus 1.6% in the placebo arm. No exacerbation of residual chemotherapy related side-effects was evident when Tarceva was used in the maintenance setting immediately following the completion of a first-line chemotherapy regimen.

SATURN Regulatory Authority Filings

In March, OSI submitted a supplemental New Drug Application (sNDA) for the use of Tarceva as a first-line maintenance treatment for patients with advanced non-small cell lung cancer (NSCLC) who have not progressed following first-line treatment with platinum-based chemotherapy. Additionally, Roche, OSI’s international partner for Tarceva, filed an application in Europe with the European Medicines Agency (EMEA). Both the U.S. and EU submissions are based on the Phase III SATURN data.

ASCO Presentations

Data are being released co-incident with the publication of on-line abstracts by the American Society of Clinical Oncology (ASCO) in advance of their Annual Meeting in Orlando, May 29-June 2, 2009. The data will be presented in an oral presentation by F. Cappuzzo, M.D., medical oncologist and principal investigator of the SATURN study (Abstract #8001) on May 31, 2009 at 9:15a.m. EDT. Biomarker analyses from the SATURN study will be presented in a poster session by Dr. W. Brugger (Abstract #8020) on June 1, 2009 between 8a.m and noon EDT.

Additional First-line Maintenance Study: ATLAS

Results will also be presented from ATLAS, a second positive Phase III study evaluating Tarceva in the first-line maintenance setting, at ASCO. ATLAS showed that people lived longer without their cancer getting worse when taking the daily pill Tarceva in combination with Avastin compared with Avastin plus placebo, following initial treatment with Avastin plus chemotherapy. The ATLAS data will be presented in a late-breaking session by Vincent A. Miller, M.D., associate attending physician, Memorial Sloan-Kettering (Abstract #LBA8002) on Sunday, May 31, 2009 at 9:30a.m EDT.

About SATURN

SATURN is an international, placebo-controlled, randomized, double-blind, Phase III study conducted by Roche that enrolled 889 patients with advanced NSCLC at approximately 160 sites worldwide. Patients were treated with four cycles of standard first-line platinum-based chemotherapy and were then randomized to Tarceva (150 mg) or placebo if their cancer did not progress. The primary endpoint of the study was progression-free survival in the overall population, as determined by investigators, and was defined as the length of time from randomization to disease progression or death from any cause. The co-primary endpoint was PFS in patients with EGFR positive tumors by IHC. Secondary endpoints included overall survival, safety and an evaluation of exploratory biomarkers, including EGFR mutations and K-ras mutations.

About Lung Cancer

According to the American Cancer Society (ACS), lung cancer is the single largest cause of cancer death among men and women in the U.S. and nearly 159,390 Americans are expected to die from

the disease in 2009. Most people with lung cancer are diagnosed with advanced stage disease that cannot be surgically removed or has spread to other parts of the body. The majority of people with advanced lung cancer survive less than one year.  NSCLC is the most common type of lung cancer.

About Tarceva

Tarceva is a once-a-day pill that targets the EGFR pathway. Tarceva is designed to inhibit the tyrosine kinase activity of the EGFR signaling pathway inside the cell, one of the critical growth factors in NSCLC and pancreatic cancers. Tarceva is indicated as a monotherapy for patients with locally advanced or metastatic NSCLC whose disease has progressed after one or more courses of chemotherapy. Results from two multicenter, placebo-controlled, randomized Phase III trials conducted in first-line patients with locally advanced or metastatic NSCLC showed no clinical benefit with the concurrent administration of Tarceva with platinum-based chemotherapy (carboplatin and paclitaxel or gemcitabine and cisplatin) and its use is not recommended in that setting.

In pancreatic cancer, Tarceva is indicated in combination with gemcitabine for the first-line treatment of patients with locally advanced pancreatic cancer, pancreatic cancer that cannot be surgically removed or pancreatic cancer that has spread to distant body organs.

Tarceva Safety

There have been infrequent reports of serious Interstitial Lung Disease (ILD)-like events including deaths in patients taking Tarceva. Serious side effects (including deaths) in patients taking Tarceva include liver and/or kidney problems; gastrointestinal (GI) perforations (the development of a hole in the stomach, small intestine, or large intestine); and severe blistering skin reactions including cases similar to Stevens-Johnson syndrome. Patients taking Tarceva plus gemcitabine were more likely to experience bleeding and clotting problems such as heart attack or stroke. Eye irritation and damage to the cornea have been reported in patients taking Tarceva. Women should avoid becoming pregnant and avoid breastfeeding while taking Tarceva. Patients should call their doctor right away if they have these signs or symptoms: new or worsening skin rash; serious or ongoing diarrhea, nausea, loss of appetite, vomiting, or stomach pain; new or worsening shortness of breath or cough; fever; eye irritation. Rash and diarrhea were the most common side effects associated with Tarceva in the non-small cell lung cancer clinical study. Fatigue, rash, nausea, loss of appetite, and diarrhea were the most common side effects associated with Tarceva plus gemcitabine therapy in the pancreatic cancer clinical study.

About OSI Pharmaceuticals

OSI Pharmaceuticals is committed to “shaping medicine and changing lives” by discovering, developing and commercializing high-quality, novel and differentiated targeted medicines designed to extend life and improve the quality of life for patients with cancer and diabetes/obesity.

This news release contains forward-looking statements. These statements are subject to known and unknown risks and uncertainties that may cause actual future experience and results to differ materially from the statements made. Factors that might cause such a difference include, among others, OSI’s and its collaborators’ abilities to effectively market and sell Tarceva and to expand the approved indications for Tarceva, OSI’s ability to protect its intellectual property rights, safety concerns regarding Tarceva, competition to Tarceva and OSI’s drug candidates from other biotechnology and pharmaceutical companies, the completion of clinical trials, the effects of FDA and other governmental regulation, including pricing controls, OSI’s ability to successfully develop and commercialize drug candidates, and other factors described in OSI Pharmaceuticals’ filings with the Securities and Exchange Commission.

EX-99.3

Exhibit 99.3

	NEWS RELEASE
Contacts:
OSI Pharmaceuticals, Inc.	Burns McClellan, Inc. (representing OSI)
Kathy Galante (investors/media)	Justin Jackson/Kathy Nugent (media)
Senior Director	212-213-0006
631-962-2043
Kim Wittig (media)
Director
631-962-2135

OSI PHARMACEUTICALS PROVIDES UPDATE ON OSI-906 DATA BEING
PRESENTED ON MAY 30^TH AT THE UPCOMING ANNUAL MEETING OF
THE AMERICAN SOCIETY OF CLINICAL ONCOLOGY (ASCO)

— OSI-906, a Potential First-in-Class Oral IGF-1R Inhibitor, Shows Encouraging Indications
of Anti-Tumor Activity in On-going Phase I Program —

MELVILLE, NEW YORK — May 15, 2009 — OSI Pharmaceuticals, Inc. (NASDAQ: OSIP) announced today preliminary data from two Phase I dose escalation studies of oral OSI-906, a small molecule insulin like growth factor-1 receptor (IGF-1R) tyrosine kinase inhibitor, in patients with advanced solid tumors. The studies, along with a third on-going Phase I trial assessing OSI-906 in combination with Tarceva, comprise part of the Company’s principal oncology development program targeting the IGF-1R. The program also includes translational research and biomarker development activities around this highly attractive oncology target. In an intermittent oral dosing study, OSI-906 was well-tolerated up to doses of 450mg and has provided preliminary evidence of anti-tumor activity, with one confirmed partial response in an adrenocortical carcinoma (ACC) patient; one minor response in a patient with non-small cell lung cancer (NSCLC); 14 patients with stabilization of their disease for longer than 12 weeks including 7 patients with stabilization of their disease for longer than 24 weeks (out of 27 patients evaluable for tumor response to date). In a continuous dosing study, OSI-906 also had an acceptable safety profile and disease stabilization for longer than 12 weeks has been observed in 8 out of 29 patients evaluable for tumor response to date. Both Phase I studies continue to accrue patients at higher doses to determine the maximum tolerated dose (MTD) for both intermittent and continuous dosing of OSI-906, and to establish a recommended dose and dosing schedule for a Phase II clinical trial of OSI-906.

“We believe these data, along with early data from an additional combination Phase I study with Tarceva, continue to position OSI-906 as a potential first-in-class small molecule inhibitor of the IGF-1R,” stated Colin Goddard, Ph.D., Chief Executive Officer of OSI Pharmaceuticals. “Our extensive research around this crucial oncology signaling target has led us to develop a comprehensive development effort that includes targeting tumors such as ACC and ovarian cancer, where IGF-2 over-expression could indicate a particular dependence on this signaling pathway, and

also NSCLC, where our understanding of EMT and compensatory signaling mechanism suggest that a Tarceva/OSI-906 combination could be particularly effective. With continued progress in our program we believe we could begin two registration-oriented trials — a monotherapy study in ACC in 2009 and a Tarceva combination study in NSCLC in 2010.”

The OSI-906 Phase I single-agent data will be presented in two poster presentations at the Annual Meeting of the American Society of Clinical Oncology (ASCO) in Orlando, FL on May 30, 2009 between 8a.m to noon EDT (Abstracts #3544 and #2559).

Study Results

Preliminary activity in adrenocortical tumor (ACC) in phase I dose escalation study of intermittent oral dosing of OSI-906, a small molecule insulin like growth factor -1 receptor (IGF-1R) tyrosine kinase inhibitor in patients with advanced solid tumors- C.P. Carden, et al. (Abstract #3544)

The primary objective of this study (OSI-906-102) is to determine the maximum tolerated dose (MTD) and recommended Phase II dose of oral OSI-906 for three intermittent dosing schedules: Schedule 1: days 1-3, every 14 days; Schedule 2: days 1-5, every 14 days; Schedule 3: days 1-7, every 14 days. Secondary objectives include safety profile, pharmacokinetics (PK) and pharmacodynamics (PD) profiles and preliminary anti-tumor activity.

Preliminary results from 33 patients evaluable to date showed that OSI-906 was well-tolerated up to doses of 450 mg, with no dose limiting toxicities (DLTs) and no grade 3 or 4 toxicities reported to date. Most common adverse events were grade 1 rash, diarrhea, fatigue and peripheral edema. Frequency and severity of toxicities did not correlate with dose level. Two cases of hyperglycemia (one grade 1; one grade 2) were reported.

Encouraging anti-tumor activity was seen in the study, with one partial response in an ACC patient at the 450mg dose (in the Schedule 1 group), 14 patients with stable disease for > 12 weeks including 7 patients with stable disease for > 24 weeks. Of particular note, anti-tumor activity was seen in two ACC patients and one NSCLC patient:

- One 2^nd-line ACC patient, a 35-year old woman with metastatic disease, had a partial response (PR) confirmed at 16 weeks of treatment with OSI-906. No drug-related toxicities have been observed to date and this patient continues on therapy.

- One 4^th-line NSCLC patient, a 77-year old man with metastatic disease, had a minor response per the treating physician and a best response (per RECIST) of stable disease for 43 weeks.

- One 3^rd-line ACC patient had stable disease for 30 weeks.

The study authors also note that PK is dose-proportional up to 450mg. An exploratory analysis from glucose monitoring also indicates that significant hyperglycemia was not observed in patients in spite of hyperinsulinemia at higher doses.

The MTD in this study has not yet been reached and patient accrual is on-going.

Phase I dose escalation study of continuous oral dosing of OSI-906, an insulin like growth factor-1 receptor (IGF-1R) tyrosine kinase inhibitor, in patients with advanced solid tumors- C.R. Lindsay, et al. (Abstract #2559)

The primary objective of this study (OSI-906-101) is to determine the MTD and recommended Phase II dose of oral OSI-906 administered either once daily or twice daily. Secondary objectives also included safety profile, PK and PD profiles and preliminary anti-tumor activity.

Preliminary results from 37 patients with advanced solid tumors (9 colorectal, 6 pancreatic, 3 renal, 3 esophageal and 16 other tumor types) also show that continuous oral dosing of OSI-906, given either once or twice a day, has an acceptable safety profile. One recent DLT of asymptomatic grade 3 hyperglycemia was reported at the 450mg once-a-day dose, however, this patient was asymptomatic and glucose returned to normal by Day 2, and no dose interruptions or reductions were necessary. OSI-906 plasma concentrations exceed concentration required for anti-tumor efficacy in preclinical models, with twice-a-day dosing providing improved coverage above threshold. Further, PD target modulation and disease stabilization were observed. While no objective tumor responses have been reported to date, 8 patients had stable disease > 12 weeks including 4 patients who had stable disease > 24 weeks.

The MTD in this study has not yet been reached and patient accrual is on-going.

Additional Background on OSI-906

IGF-1 and IGF-2 are growth factors, or hormones, known to stimulate growth and survival of cancerous cells. IGF-1R has been viewed as an important therapeutic target due to its involvement in the growth and proliferation of a variety of human cancers, including colorectal, prostate, non-small cell lung, breast and ovarian cancers.

In preclinical studies, OSI-906 blocked the ability of IGF-1R to signal in xenograft mouse models of human colorectal cancer. Preclinical research also showed that colon cancer tumor cells respond to OSI-906 because they produce and are dependent on the growth-promoting effects of IGF-2. In addition to colorectal cancer, OSI-906 has also been shown to inhibit growth of human pancreatic and thyroid cancers in animal models. The IGF/IGF-1R signaling pathway has also been implicated in protecting tumor cells from apoptosis induced by a number of cytotoxic agents as well as molecular targeted therapies including EGFR inhibitors. Preclinical data also suggest that OSI-906 may be synergistic with Tarceva in non-small cell lung and pancreatic human tumor xenografts.

About OSI Pharmaceuticals

OSI Pharmaceuticals is committed to “shaping medicine and changing lives” by discovering, developing and commercializing high-quality, novel and differentiated targeted medicines designed to extend life and improve the quality of life for patients with cancer and diabetes/obesity.

This news release contains forward-looking statements. These statements are subject to known and unknown risks and uncertainties that may cause actual future experience and results to differ materially from the statements made. Factors that might cause such a difference include, among others, OSI’s and its collaborators’ abilities to effectively market and sell Tarceva and to expand the approved indications for Tarceva, OSI’s ability to protect its intellectual property rights, safety concerns regarding Tarceva, competition to Tarceva and OSI’s drug candidates from other biotechnology and pharmaceutical companies, the completion of clinical trials, the effects of FDA and other governmental regulation, including pricing controls, OSI’s ability to successfully develop and commercialize drug candidates, and other factors described in OSI Pharmaceuticals’ filings with the Securities and Exchange Commission.