Atara Biotherapeutics, Inc. (Nasdaq: ATRA; LSE: 0HIY) is a leading off-the-shelf, allogeneic T-cell immunotherapy company that develops novel therapies targeting cancer, autoimmune conditions, and viral diseases using its proprietary Epstein-Barr virus (EBV) T-cell platform, which requires no T-cell receptor or human leukocyte antigen gene editing. Founded in 2012 and headquartered in Thousand Oaks, California, the company offers Ebvallo (tabelecleucel or tab-cel), the first approved allogeneic T-cell immunotherapy for Epstein-Barr virus positive post-transplant lymphoproliferative disease (EBV+ PTLD) in patients aged two years and older after prior rituximab or chemotherapy in Europe; investigational allogeneic CD19 CAR T immunotherapy ATA3219 for B-cell malignancies and autoimmune diseases featuring a next-generation 1XX CAR co-stimulatory domain; and ATA3431, an allogeneic bispecific CAR T targeting CD19 and CD20 for B-cell malignancies and autoimmune disease. Atara operates globally, with commercialization partnerships in Europe and regulatory activities underway in the United States, serving patients with difficult-to-treat conditions through scalable manufacturing capable of producing over a thousand doses from one donor. Recent developments include the October 2025 transfer of substantially all tab-cel regulatory activities, including Biologics License Application sponsorship, to partner Pierre Fabre Laboratories ahead of a U.S. FDA Priority Review PDUFA target action date of January 10, 2026, unlocking a potential $40 million milestone payment upon approval and double-digit tiered royalties on net sales; multiple workforce reductions in 2025, including a 29% cut in October to approximately 15 essential employees and prior 50% layoffs in March following FDA clinical holds, driving projected full-year 2025 operating expenses down by at least 60% from 2024; board changes in September 2025 appointing Greg Ciongoli as Chair amid three director exits to align with reduced scale; a $36 million registered direct offering in September 2024; and an ongoing evaluation of strategic alternatives to maximize shareholder value.