ATA-3219

U.S. FDA issues clinical hold on EBVALLO ™ (tabelecleucel) and ATA3219 studies linked to EBVALLO Complete Response Letter (CRL) THOUSAND OAKS, CA, USA I January 21, 2025 I Atara Biotherapeutics, Inc. (Nasdaq: ATRA), a leader in T-cell immunotherapy, leveraging its novel allogeneic Epstein-Barr virus (EBV) T-cell platform to develop transformative therapies for patients with cancer and autoimmune diseases, today announced that the U.S. Food and Drug Administration (FDA) has placed a clinical hold on Atara’s active Investigational New Drug (IND) applications. These INDs include the EBVALLO TM (tabelecleucel) program as monotherapy treatment for adult and pediatric patients two years of age and older with Epstein-Barr virus positive post-transplant lymphoproliferative disease (EBV+ PTLD), as well as ATA3219, an allogeneic CD19-targeted CAR-T therapy, for the treatment of non-Hodgkin’s lymphoma and systemic lupus erythematosus. Specifically identified subjects currently enrolled in the clinical studies who have the potential to derive clinical benefit may continue to receive treatment in accordance with the ongoing study protocols. Screening and enrollment of new participants in both programs have been paused. The clinical hold for EBVALLO is directly linked to inadequately addressed GMP compliance issues identified during the pre-license inspection of the third-party manufacturing facility referenced in the Complete Response Letter (CRL) for EBVALLO that was announced on January 16, 2025. While ATA3219 drug product is manufactured at a separate, fully compliant GMP-certified facility, the starting materials used in its production are affected by the compliance issues at the same third-party facility referenced in the CRL. These issues, which underlie both the CRL and the clinical hold, are specific to the referenced third-party manufacturing facility and do not affect Atara’s second third-party manufacturer, FUJIFILM Diosynth Biotechnologies (FDB) facility in Thousand Oaks, California. The FDB facility remains a critical component of Atara’s long-term manufacturing strategy for both assets. Atara and FDA have discussed and agreed upon the actions necessary to release the clinical holds. The FDA has confirmed its commitment to working collaboratively and expeditiously with Atara to resolve the clinical holds. “We intend to work closely with the FDA to address these issues as expeditiously as possible,” said Cokey Nguyen, Ph.D., President and Chief Executive Officer of Atara. “We are encouraged with ongoing correspondence with the Agency and a potential path to submitting the necessary data to release the clinical hold. Patient safety remains our priority and maintaining the highest standards for our programs.” About Atara Biotherapeutics, Inc. Atara is harnessing the natural power of the immune system to develop off-the-shelf cell therapies for difficult-to-treat cancers and autoimmune conditions that can be rapidly delivered to patients from inventory. With cutting-edge science and differentiated approach, Atara is the first company in the world to receive regulatory approval of an allogeneic T-cell immunotherapy. Our advanced and versatile T-cell platform does not require T-cell receptor or HLA gene editing and forms the basis of a diverse portfolio of investigational therapies that target EBV, the root cause of certain diseases, in addition to next-generation AlloCAR-Ts designed for best-in-class opportunities across a broad range of hematological malignancies and B-cell driven autoimmune diseases. Atara is headquartered in Southern California. For more information, visit atarabio.com and follow @Atarabio on X and LinkedIn . SOURCE: Atara Biotherapeutics