Marker Therapeutics Treats First Patient In Off-the-Shelf MAR-T Cell Program; Reports Positive Safety Data From RAPID Trial

Marker Therapeutics, Inc., a clinical-stage immuno-oncology company developing next-generation T cell-based immunotherapies for hematologic and solid tumors, announced that the first patient has been treated in its off-the-shelf (OTS) program with promising preliminary safety results.

“The initiation of our OTS program represents a major achievement,” said Juan Vera, M.D., President and CEO of Marker Therapeutics. “One of the biggest limitations to cell therapy is the time-consuming manufacturing of individualized products. With our OTS product, we aim to eliminate this bottleneck and offer a rapid treatment option for patients with aggressive and rapidly progressing diseases. We believe that using commercially available leukapheresis material from healthy donors can facilitate large-scale manufacturing and expedite treatment as fast as 72 hours, while also enabling broader scalability and accessibility of cell therapies at a lower per-dose cost.”

The company is evaluating MT-401, a multi-antigen recognizing (MAR) T cell therapy targeting four tumor-associated antigens, in the Phase 1 RAPID study. The first participant received the OTS product at the initial dose level of 100x10⁶ cells and was monitored for 28 days. Treatment was well tolerated with no therapy-related adverse events, consistent with previously reported favorable safety data for MAR-T cells. The current study focuses on patients with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS), with plans for potential expansion into additional indications.

“Having a rapid available alternative to individualized T cell production allows us to broaden our clinical investigation of MAR-T cells and to extend the OTS program to other indications,” commented Dr. Vera. “Looking ahead, we will remain focused on advancing our clinical investigation of MAR-T cells in lymphoma. We recently reported promising clinical efficacy and durability data from our APOLLO study where we have observed an objective response rate of 66%, with durable complete responses in patients with non-Hodgkin lymphoma, and we believe our lymphoma program has the potential to qualify for expedited approval.”

The OTS program is supported by non-dilutive funding from the U.S. Food and Drug Administration (FDA), National Institutes of Health (NIH) Small Business Innovation Research (SBIR) program, and the Cancer Prevention and Research Institute of Texas (CPRIT). Marker’s cellular inventory, derived from commercially available leukapheresis material and designed for partial HLA matching, enables scalable patient access. Data from the RAPID trial will inform future development of MAR-T cell products and support broader clinical applications. Meanwhile, the company continues advancing its lead asset, MT-601, in the ongoing Phase 1 APOLLO study in lymphoma, which has shown durable clinical responses and a favorable safety profile.

“Behind this milestone is a set of scientific data and a significant body of research and development. This strategy has been extensively tested in the clinic at Baylor College of Medicine, specifically in the context of virus-specific T cells (VST). As we enroll additional patients in the Phase 1 RAPID study, we will continue to closely monitor the safety and long-term treatment effects of our OTS product. The collected data from this trial will serve as a foundation for refining and understanding the performance of MAR-T cells as an OTS product to potentially expand the OTS approach to other product candidates in our pipeline with the goal to accelerate time to treatment in other indications,” concluded Dr. Vera.