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January 4 , 2021 ATARA BIO Atara Biotherapeutics Provides Regulatory Update for Tab - Cel® for Epstein - Barr Virus - Positive Post - Transplant Lymphoproliferative Disease Company to Host Conference Call on January 4th at 8:30 a.m. EST SOUTH SAN FRANCISCO , Calif .-- ( BUSINESS WIRE ) -- Atara Biotherapeutics , Inc. ( Nasdaq : ATRA ; the " Company " ) , a pioneer in T - cell immunotherapy leveraging its novel allogeneic EBV T - cell platform to develop transformative therapies for patients with severe diseases including solid tumors , hematologic cancers and autoimmune diseases , today noted that it has not yet initiated the Biologics License Application ( BLA ) submission for tab - celⓇ ( tabelecleucel ) , currently in Phase 3 development for Epstein - Barr virus - positive post- transplant lymphoproliferative disease ( EBV * PTLD ) . The Company remains on track to complete the BLA filing in Q3 2021 , based on several key points of agreement with FDA as previously announced . To initiate the BLA , Atara is awaiting a procedural decision from the FDA related to how the historical non - pivotal data should be presented in the BLA submission . Following the FDA agreement in October 2020 that the pivotal 302 ALLELE data will be the primary basis for approval , and that historical non - pivotal clinical data will be supportive , FDA needs to decide whether they view the drug product manufactured by our academic partner used in historical , non - pivotal studies as comparable to the drug product manufactured by Atara used in the pivotal ALLELE study . This decision will then determine if the Company will submit in the clinical module the pivotal and non - pivotal data combined in pooled analyses or separately in parallel analyses . The type of analysis does not change expectations regarding the proposed product indication for previously treated patients with EBV + PTLD . The initial module for the rolling BLA for tab - cel® has been ready for submission since early December , and its content is not impacted by this decision . The Company remains on track to complete the BLA filing in Q3 2021 and is simply awaiting this procedural decision from FDA to initiate the BLA . " Based on prior conversation with FDA , we had the understanding that this procedural decision would be made by the end of 2020 so we could initiate the BLA as planned . This procedural decision has not yet been communicated by FDA , and we look forward to continuing our constructive dialogue with the agency as part of our BTD status , " said Pascal Touchon , President and Chief Executive Officer of Atara . " We remain on track to complete the BLA filing in Q3 2021. " The Company expects this procedural decision to be taken soon by FDA , based on the ongoing , constructive dialogue with the agency , which has already resulted in several key