Weitao Biologics Announces Positive Initial Clinical Data for GT801, an In Vivo Anti-CD19 CAR-T Therapy, at ASH 2025

Recently, IVACTA Biotechnology (a biotechnology company spun off from Gracell Biotechnologies, focusing on the development of in vivo CAR-T therapies for cancer and autoimmune diseases) announced positive data from the GT801 clinical trial initiated by investigators (IIT study). GT801 is an innovative anti-CD19 in vivo CAR product that delivers optimized mRNA through T cell-targeted LNP. Professor Pin Wang, Chief Scientific Officer of Gracell Biotechnologies, was invited to present the latest research progress at the 2025 American Society of Hematology (ASH) Annual Meeting in Orlando, Florida, in an oral presentation titled "Precision In Vivo CAR-T Generation via CLAMP-enabled mRNA Delivery: Toward Scalable and Translatable Cell Therapy." The presentation highlighted the early clinical drug activity of GT801 and its potential to redefine the delivery approach for CAR-T therapy.

In a Phase I clinical trial initiated by the investigator, the safety, tolerability, and preliminary efficacy of GT801 in treating patients with relapsed/refractory CD19-positive B-cell lymphoma under repeated dosing conditions were evaluated. As of November 30, 2025, two non-Hodgkin lymphoma patients who did not receive lymphodepletion pretreatment successfully completed multiple administrations of GT801. The first enrolled patient received three infusions of 0.5 mg each of the GT801 product, while the second patient received four doses of 1.5 mg each. Overall, the clinical manifestations showed good tolerability, high CAR expression levels in peripheral blood T cells, and persistent and reproducible CAR-T expansion after each administration. No CAR expression was detected in peripheral blood mononuclear cells, indicating no off-target delivery risk for GT801. This confirms that the T-LNP delivery platform can sufficiently ensure enhanced targeting efficiency while avoiding non-specific uptake.

GT801 demonstrated rapid and efficient pharmacokinetics, effectively depleting B cells in peripheral blood and various tissues. Bone marrow and lymph node biopsies from both patients showed effective B-cell clearance. By the fourth week after multiple dosing, both patients achieved partial remission.

Dr. Yarong Liu, founder and CEO of IVACTA Biotechnology, stated: "In non-Hodgkin lymphoma patients who have failed multiple lines of therapy, we have observed good safety and encouraging efficacy of GT801. These findings demonstrate that GT801 can achieve high CAR-T activity and sustainable expansion in vivo without the need for lymphodepletion preconditioning. This helps us take an important step forward in developing large-scale production, improving patient accessibility, and achieving commercial feasibility."

About GT801

GT801 is an innovative anti-CD19 in vivo CAR product that delivers optimized mRNA through T cell-targeting LNPs. This platform integrates the CLAMP technology co-developed by Grail Bio and Vzet Biotech, enabling precise and quantitative conjugation of T cell-targeting VHH antibodies with LNPs. This enhances targeting efficiency while avoiding non-specific uptake, promoting specific and efficient CAR expression and maximizing the functionality of in vivo generated CAR-T cells. GT801 aims to directly generate potent and durable CAR-T cells within patients, supporting repeated dosing to achieve a low-cost, highly effective, and easy-to-use clinical solution, overcoming the high cost and long cycle commercialization bottlenecks associated with ex vivo cell manufacturing processes.

Grail Bio was founded in 2019 as an innovative pharmaceutical company focused on tumor immunotherapy, with a research and development pipeline represented by TIL drugs. Grail Bio has completed multiple rounds of equity financing and received support from several well-known venture capital funds both in China and internationally.

GT101 Injection, independently developed by IVACTA Biotechnology, is the first TIL drug in China to be approved for registrational clinical trials and has now entered the pivotal Phase II clinical trial. GT201 Injection, the world's first membrane-bound IL-15 complex-engineered TIL product developed by IVACTA Biotechnology, has completed dual IND submissions in both China and the United States. The company’s core R&D platforms include the StemTexp® Stem-like TIL Expansion Technology Platform, StaViral® Stable Viral Production System, ImmuT Finder® Immunomodulatory Target Discovery Platform, and KOReTIL® High-efficiency Gene Knockout System. Based on these platforms, a series of next-generation gene-edited TIL drugs have been developed. IVACTA Biotechnology possesses internationally leading technical reserves and industrial resources, aiming to create groundbreaking cellular therapies for solid tumors, bringing new hope to cancer patients worldwide.

IVACTA Biotechnology was founded on June 25, 2025, as a spin-off of the in vivo CAR-T platform from Beijing Gracell Biomedicines Co., Ltd. ("Gracell Biomedicines"). IVACTA Biotechnology is developing an in vivo CAR-T pipeline based on a T-cell-targeted LNP delivery system, focusing on bringing revolutionary treatments to hematological malignancies and autoimmune diseases.