FDA Places Clinical Hold On Atara Biotherapeutics' Two Cell Therapy Programs

Atara Biotherapeutics (ATRA) faced a significant setback on January 22, 2025, as the U.S. Food and Drug Administration (FDA) placed a clinical hold on the company's two cell therapy programs: EBVALLO™ (tabelecleucel) and ATA3219. The hold affects the development of EBVALLO for Epstein-Barr virus positive post-transplant lymphoproliferative disease (EBV+ PTLD) and ATA3219 for non-Hodgkin's lymphoma and systemic lupus erythematosus.

The clinical hold is directly linked to inadequately addressed Good Manufacturing Practice (GMP) compliance issues identified during the pre-license inspection of a third-party manufacturing facility. While ATA3219's 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 Complete Response Letter (CRL) for EBVALLO. 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.

Atara and the FDA have agreed upon the actions necessary to release the clinical holds, with the FDA committing to working collaboratively and expeditiously with Atara to resolve the issues. The company has stated that it intends to work closely with the FDA to address these concerns as expeditiously as possible.

The pause in new enrollment for Atara's cell therapy programs will likely impact their clinical development timelines and potential commercialization prospects. With the clinical hold in place, Atara cannot enroll new patients into these studies, which means that the collection of data needed to support regulatory submissions and advance these therapies through clinical trials will be delayed. This could potentially impact the regulatory approval timelines for these therapies and their commercialization prospects.

Atara's stock price has been volatile in recent months, reflecting the uncertainty surrounding the company's pipeline and regulatory setbacks. As of January 22, 2025, ATRA stock was trading at $12.50 per share, down from its 52-week high of $25.50 but up from its 52-week low of $8.50.




In conclusion, the FDA's clinical hold on Atara Biotherapeutics' two cell therapy programs represents a significant regulatory setback for the company. The pause in new enrollment will impact the clinical development timelines and potential commercialization prospects of these therapies. Atara must now focus on addressing the GMP compliance issues and working with the FDA to regain approval for further clinical development. Investors should closely monitor the company's progress in resolving these issues and the potential impact on its stock price.