First Allogeneic T-Cell Therapy BLA Submission to U.S. Food and Drug Administration

If Approved, Tab-cel Would be First Approved Therapy in U.S. for EBV+ PTLD

Acceptance of BLA Will Trigger $20 Million Milestone Payment from Pierre Fabre Laboratories, with Potential for Additional $60 Million Milestone Upon FDA Approval

THOUSAND OAKS, CA, USA I May 20, 2024 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 Atara has submitted a Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) for tabelecleucel (tab-cel®) indicated as monotherapy for treatment of adult and pediatric patients two years of age and older with Epstein-Barr virus positive post-transplant lymphoproliferative disease (EBV+ PTLD) who have received at least one prior therapy. For solid organ transplant patients, prior therapy includes chemotherapy unless chemotherapy is inappropriate. There are no FDA approved therapies in this treatment setting.

“The BLA submission for tab-cel represents a significant moment for Atara, our partner Pierre Fabre, and the broader allogeneic T-cell therapy field, and is a critical step towards our goal of delivering this first-of-its-kind treatment to EBV+ PTLD patients in the U.S.,” said Pascal Touchon, President and Chief Executive Officer of Atara. “I would like to thank the patients and physicians who participated in the tab-cel clinical trials, our long-time collaborators at Memorial Sloan Kettering Cancer Center, as well as our internal teams for their remarkable dedication and hard work. We now look forward to continued collaboration with the FDA on its review and with Pierre Fabre as they actively prepare for the potential launch of this innovative therapy in the U.S.”

Tab-cel is an allogeneic, EBV-specific T-cell immunotherapy designed to target and eliminate EBV-infected cells. The BLA is supported by pivotal and supportive data covering more than 430 patients treated with tab-cel across multiple life-threatening diseases including the latest pivotal ALLELE study data that demonstrated a statistically significant 48.8% Objective Response Rate (ORR) (p<0.0001) and favorable safety profile consistent with previous analyses.

Tab-cel has been granted Breakthrough Therapy Designation for the treatment of rituximab-refractory EBV-associated lymphoproliferative disease by the U.S. FDA and has orphan drug designation.

In December 2023, Atara announced the closing of the expanded global partnership with Pierre Fabre Laboratories for the U.S. and remaining global commercial markets for tab-cel, building on an initial partnership covering Europe, Middle East, Africa, and other select emerging markets. With the completion of the tab-cel BLA submission, Atara continues to advance the Pierre Fabre expanded global partnership, which includes potential milestone payments of $20 million and $60 million from Pierre Fabre contingent upon the successful FDA acceptance and approval of the tab-cel BLA, respectively. In addition, Pierre Fabre is reimbursing Atara for expected tab-cel global development costs through the BLA transfer and purchasing tab-cel inventory through the manufacturing transfer date. Atara is also eligible to receive double-digit tiered royalties on net sales of tab-cel in the U.S. and remaining global commercial markets referenced above.

Tab-cel was granted marketing authorization under the brand name Ebvallo™ in December 2022 by the European Commission. Marketing authorization was also granted by the Medicines and Healthcare Products Regulatory Agency in the United Kingdom in May 2023 and by Swissmedic in Switzerland in May 2024. In all three territories, Ebvallo is indicated as monotherapy for the treatment of adult and pediatric patients two years of age and older with relapsed or refractory EBV+ PTLD who have received at least one prior therapy. For solid organ transplant patients, prior therapy includes chemotherapy unless chemotherapy is inappropriate.

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