UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE

13a-16 OR 15d-16 UNDER

THE SECURITIES EXCHANGE ACT OF 1934

For the month of February, 2024

Commission File Number  001-41666

CASI PHARMACEUTICALS, INC.

(Translation of registrant’s name into English)

1701-1702, China Central Office Tower 1

No. 81 Jianguo Road, Chaoyang District

Beijing, 100025

People’s Republic of China

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.  Form 20-F  x Form 40-F  ¨

Departure of Certain Officer

On February 8, 2024, Mr. Fuqiang Zhang tendered his resignation as the Chief Commercial Officer (the “COO”) of CASI Pharmaceuticals, Inc., a Cayman Islands incorporated company (“CASI” or the “Company”), with immediate effect. Mr. Zhang’s decision to resign was not a result of any disagreements with the Company on any matter related to the operations, policies, or practices of the Company.

The Company currently has no plan to appoint a new COO. The Company’s Global Chief Commercial Officer will continue to lead the efforts of the Company on the establish of business system and market expansion.

Forward-Looking Statements

This 6-K contains forward-looking statements. These statements are made under the “safe harbor” provisions of the U.S. Private Securities Litigation Reform Act of 1995. These forward-looking statements can be identified by terminology such as “will,” “expects,” “anticipates,” “future,” “intends,” “plans,” “believes,” “estimates,” “confident” and similar statements. The Company may also make written or oral forward-looking statements in its periodic reports to the U.S. Securities and Exchange Commission (the “SEC”), in its annual report to shareholders, in press releases and other written materials and in oral statements made by its officers, directors or employees to third parties. Statements that are not historical facts, including statements about the Company’s beliefs and expectations, are forward-looking statements. Forward-looking statements involve inherent risks and uncertainties. A number of factors could cause actual results to differ materially from those contained in any forward-looking statement. All information provided herein is as of the date of this 6-K, and the Company undertakes no obligation to update any forward-looking statement, except as required under applicable law. We caution readers not to place undue reliance on any forward-looking statements contained herein.

SIGNATURES

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, thereunto duly authorized.