[6-K] CASI Pharmaceuticals, Inc. Current Report (Foreign Issuer)

Rhea-AI Filing Summary

CASI Pharmaceuticals reported that its subsidiary, CASI Pharmaceuticals (China) Co., Ltd., received a Drug Registration Certificate from China’s National Medical Products Administration for Thiotepa for Injection. The certificate is valid until February 1, 2031, allowing commercial use of this product in mainland China.

CASI holds exclusive distribution rights for Thiotepa in China under an agreement with ESTEVE Pharmaceuticals GmbH. The company also references earlier disclosures about a contemplated sale of Thiotepa-related licensing, distribution, supply and related rights in mainland China, along with certain other pipeline products, to Kaixin Pharmaceuticals Inc..

Insights

Biopharma regulatory and strategy analyst

China Thiotepa approval adds an approved oncology asset, though CASI may divest related rights.

The receipt of a Drug Registration Certificate for Thiotepa for Injection from China’s National Medical Products Administration provides CASI with a fully registered oncology product in mainland China through February 1, 2031. This is a clear regulatory milestone.

CASI already holds exclusive distribution rights for Thiotepa in China via ESTEVE Pharmaceuticals GmbH, which positions the company to commercialize the drug or potentially enhance the value of these rights in transactions. Registration typically permits marketing, subject to commercial execution and competitive dynamics.

The company highlights prior public disclosure of a contemplated disposal of Thiotepa-related licensing, distribution, supply and associated rights, as well as certain other pipeline assets, to Kaixin Pharmaceuticals Inc.. Any completed transaction would shape how much of the long-dated Thiotepa opportunity remains with CASI versus being monetized or transferred.

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, 2026

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  ¨

INCORPORATION BY REFERENCE

The information included in this Report on Form 6-K is hereby incorporated by reference into the Company's Registration Statements on Form F-3 (File No. 333-283998 and No. 333-281621) (including any prospectuses forming a part of such registration statement) and is to be a part thereof from the date on which this Report on Form 6-K is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

CASI Pharmaceuticals Reports the Receipt of Drug Registration Certificate for Thiotepa in China

CASI Pharmaceuticals, Inc. (NASDAQ: CASI, the “Company”), a clinical-stage biopharmaceutical company developing CID-103, an anti-CD38 monoclonal antibody, for patients with organ transplant rejection and autoimmune diseases, today reported that CASI Pharmaceuticals (China) Co., Ltd. received the Drug Registration Certificate from National Medical Products Administration for Thiotepa for Injection. Such certificate shall remain valid till February 1, 2031.

The Company has exclusive distribution rights for Thiotepa in China from ESTEVE Pharmaceuticals GmbH (formerly known as RIEMSER Pharma GmbH). Please refer to the Company’s earlier public disclosure with respect to the contemplated disposal of all licensing rights, distribution rights, supply arrangements and related rights related to Thiotepa (in China excluding Hong Kong, Macau and Taiwan) and certain other pipeline products to Kaixin Pharmaceuticals Inc..

Forward-Looking Statements

This announcement 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. Among other things, the business outlook and quotations from management in this announcement, as well as the Company's strategic and operational plans, contain forward-looking 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. Further information regarding these and other risks is included in the Company's filings with the SEC. All information provided herein is as of the date of this announcement, 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.

	CASI Pharmaceuticals, Inc.
	By:	/s/ David Cory
	Name:	David Cory
	Title:	CEO
Date: February 10, 2026