CARSGEN-B - VOLUNTARY ANNOUNCEMENT - ABSTRACT OF RESEARCH RESULTS ON CT0596 AND CT1190B ACCEPTED FOR POSTER PRESENTATION AT 2026 EHA ANNUAL CONGRESS

CARsgen Therapeutics Holdings Limited

科濟藥業控股有限公司

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 2171)

VOLUNTARY ANNOUNCEMENT

ABSTRACT OF RESEARCH RESULTS ON CT0596 AND CT1190B

ACCEPTED FOR POSTER PRESENTATION AT 2026 EHA ANNUAL

CONGRESS

This announcement is made by CARsgen Therapeutics Holdings Limited (the "Company", together with its subsidiaries and consolidated affiliated entities, the "Group" or "CARsgen") on a voluntary basis to inform the shareholders and potential investors of the Company about the latest business update of the Group.

The board of directors of the Company (the "Board") announces that the research results of the IITs of CT0596 (an allogeneic CAR T-cell product targeting BCMA) for the treatment of refractory/relapse multiple myeloma (R/R MM) or plasma cell leukemia (PCL) and CT1190B (an allogeneic CAR T-cell product targeting CD19/CD20) for the treatment of refractory/relapse B-cell non-Hodgkin lymphoma (R/R B-NHL) have been accepted for poster presentation at the 2026 Annual Congress of the European Hematology Association ("EHA"). Abstracts and further details will be announced after May 12, 2026, 15:30 CEST. Further details will be provided on our corporate website www.carsgen.com.

ABOUT CT0596

CT0596 is an allogeneic BCMA-targeted CAR-T therapy developed using CARsgen's proprietary THANK-u Plus™ platform. It is currently being evaluated in IITs for R/R MM or PCL. CT0596 demonstrated preliminary favorable tolerability and encouraging efficacy signals. Further investigation is planned in additional plasma cell malignancies and autoimmune diseases mediated by autoreactive plasma cells. The Company plans to initiate Phase Ib clinical trials for R/R MM and primary PCL in 2026.

ABOUT CT1190B

CT1190B is a CD19/CD20-targeted allogeneic CAR-T cell therapy developed based on CARsgen's THANK-u Plus™ platform. Ongoing clinical trials include IITs for R/R B-NHL, and for moderate-to-severe refractory systemic lupus erythematosus (SLE) or refractory/progressive systemic sclerosis (SSc). The Company plans to initiate Phase Ib clinical trials for R/R B-NHL in 2026.

ABOUT THE COMPANY

CARsgen is a biopharmaceutical company focusing on developing innovative CAR T-cell therapies to address the unmet clinical needs including but not limited to hematologic malignancies, solid tumors and autoimmune diseases. CARsgen has established end-to-end capabilities for CAR T-cell research and development covering target discovery, preclinical research, product clinical development, and commercial-scale production. CARsgen has developed novel in-house technologies and a product pipeline with global rights to address challenges faced by existing CAR T-cell therapies. Efforts include improving safety profile, enhancing the efficacy in treating solid tumors, and reducing treatment costs, etc. CARsgen's mission is to be a global biopharmaceutical leader that provides innovative and differentiated cell therapies for patients worldwide and makes cancer and other diseases curable.

DEFINITIONS AND GLOSSARY OF TECHNICAL TERMS

"CAR" chimeric antigen receptor

"CAR T" chimeric antigen receptor T cell

"IIT" clinical trial sponsored and conducted by independent investigators

"Phase Ib" a phase of clinical trials that primarily assesses safety, tolerability and pharmacokinetics/pharmacodynamics at multiple ascending dose levels prior

to commencement of a Phase II or Phase III clinical trial

Cautionary Statement required by Rule 18A.05 of the Rules Governing the Listing of

Securities on The Stock Exchange of Hong Kong Limited: The Company cannot guarantee that it will be able to develop, or ultimately market, CT0596 and CT1190B, successfully. Shareholders and potential investors of the Company are advised to exercise caution when dealing in the shares of the Company.

Cautionary-Language Regarding Forward-Looking Statements

All statements in this announcement that are not historical fact or that do not relate to present facts or current conditions are forward-looking statements. Such forward-looking statements express the Group's current views, projections, beliefs and expectations with respect to future events as of the date of this announcement. Such forward-looking statements are based on a number of assumptions and factors beyond the Group's control. As a result, they are subject to significant risks and uncertainties, and actual events or results may differ materially from these forward-looking statements and the forward-looking events discussed in this announcement might not occur. Such risks and uncertainties include, but are not limited to, those detailed under the heading "Principal Risks and Uncertainties" in our most recent annual report and interim report and other announcements and reports made available on our corporate website, https://www.carsgen.com. No representation or warranty is given as to the achievement or reasonableness of, and no reliance should be placed on, any projections, targets, estimates or forecasts contained in this announcement.

By order of the Board

CARsgen Therapeutics Holdings Limited Dr. Zonghai LI

Chairman

Hong Kong, April 27, 2026