UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14D-9

(Rule 14d-101)

(Amendment No. 3)

Solicitation/Recommendation Statement

Under Section 14(d)(4) of the Securities Exchange Act of 1934

CTI BioPharma Corp.

(Name of Subject Company)

CTI BioPharma Corp.

(Name of Persons Filing Statement)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

12648L601

(CUSIP Number of Class of Securities)

Adam R. Craig

President, Chief Executive Officer and Interim Chief Medical Officer

3101 Western Avenue, Suite 800

Seattle, Washington 98121

(206) 282-7100

(Name, address, and telephone numbers of person authorized to receive notices and communications on behalf of the persons filing statement)

With copies to:

Graham Robinson Skadden, Arps, Slate, Meagher & Flom LLP 500 Boylston Street, 23rd Floor Boston, Massachusetts 02116 (617) 573-4800 Katherine D. Ashley Skadden, Arps, Slate, Meagher & Flom LLP 1440 New York Avenue, N.W. Washington, D.C. 20005 (202) 371-7000 Ryan A. Murr Branden C. Berns Gibson, Dunn & Crutcher LLP 555 Mission Street San Francisco, CA 94105 (415) 393-8200

☐ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

This Amendment No. 3 (this “Amendment”) amends and supplements the Solicitation/Recommendation Statement on Schedule 14D-9 (as amended or supplemented from time to time, the “Schedule 14D-9”) filed by CTI BioPharma Corp., a Delaware corporation (“CTI”) with the Securities and Exchange Commission (the “SEC”) on May 25, 2023, relating to the tender offer by Cleopatra Acquisition Corp., a Delaware corporation (“Purchaser”) and a wholly owned, indirect subsidiary of Swedish Orphan Biovitrum AB (publ), a Swedish public limited liability company (“Sobi”), to purchase all of the issued and outstanding shares of CTI common stock, par value $0.001 per share (the “Shares”), for $9.10 per Share, net to the seller in cash, without interest and subject to any applicable withholding tax, upon the terms and subject to the conditions set forth in the Offer to Purchase, dated May 25, 2023 (as amended or supplemented from time to time), and in the related Letter of Transmittal (as amended or supplemented from time to time).

Except to the extent specifically provided in this Amendment, the information set forth in the Schedule 14D-9 remains unchanged. Capitalized terms used, but not otherwise defined, in this Amendment shall have the meanings ascribed to them in the Schedule 14D-9. This Amendment No. 3 is being filed to reflect certain updates as set forth below.

ITEM 8. ADDITIONAL INFORMATION

Item 8 of the Schedule 14D-9 is hereby amended and supplemented as follows:

The following paragraph replaces the second paragraph under the heading entitled “Regulatory Approvals—Antitrust in the United States”:

“Under the HSR Act, the purchase of Shares in the Offer may not be completed until the expiration of a fifteen (15) calendar day waiting period following the filing of certain required information and documentary material concerning the Offer and the Merger with the FTC and the Antitrust Division, unless the waiting period is earlier terminated by the FTC and the Antitrust Division. If the 15th calendar day of the initial waiting period is not a business day, the initial waiting period is extended until 11:59 p.m. of the next business day. The parties agreed in the Merger Agreement to file such Premerger Notification and Report Forms under the HSR Act with the FTC and the Antitrust Division in connection with the purchase of Shares in the Offer and the Merger as promptly as reasonably practicable and advisable, but no later than ten (10) business days from the date of the Merger Agreement. Each of CTI and Sobi filed a Premerger Notification and Report Form under the HSR Act with the FTC and the Antitrust Division in connection with the purchase of Shares in the Offer and the Merger on May 25, 2023. At 11:59 p.m., Eastern Time, on June 9, 2023, the waiting period applicable to the Offer under the HSR Act expired. Accordingly, the condition to the Offer relating to the expiration or termination of the waiting period (or any extension thereof) under the HSR Act has been satisfied.”

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After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: June 12, 2023

CTI BioPharma Corp.
By:	/s/ David H. Kirske
Name:	David H. Kirske
Title:	Chief Financial Officer

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