Poseida Therapeutics, Inc. a clinical-stage cell and gene therapy company advancing a new class of treatments for patients with cancer and rare diseases, today announced the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation for the treatment of multiple myeloma to P-BCMA-ALLO1, a novel BCMA-targeted allogeneic, T stem cell memory (TSCM)-rich chimeric antigen receptor (CAR)-T therapy candidate. The Company is investigating P-BCMA-ALLO1 in partnership with Roche for the treatment of relapsed/refractory multiple myeloma (RRMM).

"The Orphan Drug Designation for P-BCMA-ALLO1 underscores the high unmet medical need for a rapid and accessible off-the-shelf allogeneic CAR-T therapy for patients with multiple myeloma," said Kristin Yarema, Ph.D., President and Chief Executive Officer of the Company. "This designation further validates our belief that TSCM-rich allogeneic CAR-T therapies may potentially offer the optimal combination of clinical results, on-demand availability, and high-volume production, while supporting broader access to CAR-T therapies. We look forward to continuing our work on the Phase 1 study of P-BCMA-ALLO1 and plan to share further clinical updates in 2024."

The Company is currently evaluating P-BCMA-ALLO1 in a Phase 1 clinical trial and recently shared positive early safety and preliminary efficacy data at the 65th American Society of Hematology (ASH) Annual Meeting and Exposition in December 2023. Data highlighted at the meeting showed that P-BCMA-ALLO1 was a well-tolerated off-the-shelf therapy with a favorable emerging safety profile, delivered to 100% of patients in the intent-to-treat population with no use of bridging chemotherapy or other anti-myeloma bridging therapies. Preliminary data presented at ASH also showed allogeneic TSCM-rich CAR-T cells trafficking to bone marrow, differentiating to cell-killing effector T cells and persisting at least 6 weeks after treatment, which support the hypothesis of cell persistence at tumor-relevant sites.

The Company will present data on a subset of recently enrolled patients refractory to initial BCMA targeting therapy in a poster presentation at the American Association for Cancer Research (AACR) Annual Meeting in San Diego on April 8, 2024, 9:00 AM to 12:30 PM PT.

Subject to coordination with Roche, the Company plans to provide an additional clinical update on the P-BCMA-ALLO1 program at a scientific meeting in the second half of 2024.

The FDA's Orphan Drug Designation program provides orphan status to drugs or biologics intended for the prevention, diagnosis, or treatment of diseases that affect fewer than 200,000 people in the United States. Sponsors of medicines that are granted Orphan Drug Designation are entitled to certain incentives, including tax credits for qualified clinical trials, prescription drug user-fee exemptions, and potential seven-year marketing exclusivity upon FDA approval.

About P-BCMA-ALLO1

P-BCMA-ALLO1 is an allogeneic CAR-T product candidate licensed to Roche targeting B-cell maturation antigen (BCMA) for the treatment of relapsed/refractory multiple myeloma. This allogeneic program includes a VH-based binder that targets BCMA and clinical data presented at ASH in December 2023 support the Company's belief that TSCM-rich allogeneic CAR-Ts have the potential to offer effective, safe, and reliable treatment addressing unmet needs in multiple myeloma. 

About Poseida Therapeutics, Inc.

Poseida Therapeutics is a clinical-stage biopharmaceutical company advancing differentiated cell and gene therapies with the capacity to cure certain cancers and rare diseases. The Company's pipeline includes allogeneic CAR-T cell therapy product candidates for both solid and liquid tumors as well as in vivo gene therapy product candidates that address patient populations with high unmet medical need. The Company's approach to cell and gene therapies is based on its proprietary genetic editing platforms, including its non-viral piggyBac® DNA Delivery System, Cas-CLOVER™ Site-Specific Gene Editing System, Booster Molecule, and nanoparticle and hybrid gene delivery technologies as well as in-house GMP cell therapy manufacturing. The Company has formed a global strategic collaboration with Roche to unlock the promise of cell therapies for patients with hematological malignancies.