Atara Biotherapeutics, Inc. (Nasdaq: ATRA) announced on March 12, 2026, that a Type A meeting with the US FDA has been scheduled to discuss the Complete Response Letter issued for the Biologics License Application for tabelecleucel, also known as tab-cel or EBVALLO, an allogeneic EBV-specific cytotoxic T-cell immunotherapy for the treatment of Epstein-Barr virus-positive post-transplant lymphoproliferative disease. Pierre Fabre Pharmaceuticals, which holds the BLA, will lead the meeting with support from Atara.
The CRL indicated that the FDA required additional evidence of effectiveness beyond what was included in the original BLA submission. Pierre Fabre and Atara stated they intend to address the agency's concerns collaboratively and pursue resubmission with additional efficacy data collected since the initial filing. Cokey Nguyen, Atara's President and Chief Executive Officer, said the company anticipates providing a regulatory update in the second quarter of 2026. The Type A meeting designation indicates the FDA recognized the urgency of the discussion, as such meetings are typically reserved for stalled programs or serious safety matters.
Tabelecleucel is an allogeneic, off-the-shelf T-cell immunotherapy derived from healthy third-party donors. The T cells are selected and expanded to recognize and destroy EBV-infected cells through their native T-cell receptors in an HLA-restricted manner. Unlike CAR T-cell therapies, tabelecleucel does not involve genetic modification. EBV-positive PTLD is a rare and often fatal complication arising after solid organ or hematopoietic cell transplantation, where immunosuppression allows uncontrolled proliferation of EBV-infected B cells. No therapy has received specific FDA approval for this indication. Current treatment relies on reduction of immunosuppression, off-label use of rituximab, and chemotherapy regimens such as R-CHOP for refractory cases.
The molecule originated from foundational research at Memorial Sloan Kettering Cancer Center. Atara Biotherapeutics licensed the technology from MSK and advanced tabelecleucel through clinical development. In 2024, Pierre Fabre acquired global rights to the program from Atara, assuming responsibility for commercialization, regulatory strategy, and further development. Atara retains a supporting role in the partnership.