Poseida Therapeutics has received the Regenerative Medicine Advanced Therapy (RMAT) designation from the US Food and Drug Administration (FDA) for its investigational stem cell memory (TSCM) T cell-based allogeneic CAR [chimeric antigen receptor]-T cell therapy, P-BCMA-ALLO1.

This therapy is currently in Phase I/Ib clinical development for patients with relapsed/refractory multiple myeloma.

The RMAT designation, which encompasses the benefits of both the fast track and breakthrough therapy programmes, is based on encouraging early data from the Phase I study of P-BCMA-ALLO1, which has shown potential in efficacy and safety profile, as well as rapid "off-the-shelf" accessibility for patients.

Poseida Therapeutics CEO and president Kristin Yarema stated: "The RMAT designation for P-BCMA-ALLO1, our lead programme, is based on impressive early clinical data from our ongoing Phase 1 study and further validates its potential to address the unmet needs of patients with relapsed/refractory multiple myeloma.

"Importantly, our data has shown clinical responses in very sick, refractory patients, including those that have received prior BCMA-targeted therapies. With both RMAT and orphan drug designations for P-BCMA-ALLO1, we look forward to working closely with the FDA as we continue to advance this next-generation, off-the-shelf allogeneic CAR-T therapy, including the recently initiated Phase 1b portion of the trial."

Poseida Therapeutics is set to present new clinical data from the Phase I study at the 21st International Myeloma Society Annual Meeting in Rio de Janeiro from 25 to 28 September 2024.

Further clinical updates on P-BCMA-ALLO1 are anticipated in the second half of 2024. These updates will be co-ordinated with Roche, which has entered a strategic collaboration with Poseida for multiple investigational allogeneic CAR-T therapies targeting blood cancers.

P-BCMA-ALLO1, an allogeneic CAR-T product candidate targeting B-cell maturation antigen (BCMA), is licensed to Roche for the treatment of relapsed/refractory multiple myeloma.

The allogeneic programme features a VH-based binder targeting BCMA.

Clinical data presented at the American Society of Hematology (ASH) meeting in December 2023 support the potential of TSCM-rich allogeneic CAR-Ts to offer effective and safe treatments for multiple myeloma.

The FDA's RMAT designation for P-BCMA-ALLO1 applies to adult patients with relapsed/refractory multiple myeloma who have undergone at least three prior lines of therapies, including a proteasome inhibitor, an immunomodulatory agent and an anti-CD38 antibody. The therapy has also received orphan drug designation for multiple myeloma.