Atara Biotherapeutics Provides Update on Strategic Collaboration with Bayer

Atara Biotherapeutics, Inc. (Nasdaq: ATRA), a leader in T-cell immunotherapy, leveraging its novel allogeneic EBV T-cell platform to develop transformative therapies for patients with cancer and autoimmune diseases, today announced that it received notification of Bayer’s intention to end the exclusive worldwide licensing agreement for next-generation mesothelin-directed CAR T-cell therapies.

The collaboration included the funding and development of ATA3271, an armored allogeneic T-cell immunotherapy, and an autologous version, ATA2271, for high mesothelin-expressing tumors such as malignant pleural mesothelioma and non-small-cell lung cancer. Both ATA2271 and ATA3271 incorporate Atara’s novel inclusion of armoring in the form of a PD-1 DNR construct to overcome checkpoint inhibition and a 1XX costimulatory domain on the CAR to enhance expansion and functional persistence of the CAR T-cells. ATA3271 leverages Atara’s EBV T-cell platform and is currently in IND (Investigational New Drug)-enabling studies.

“We acknowledge Bayer’s decision to end our collaboration following Bayer’s strategic review and asset-level prioritization of its pipeline, including cell and gene therapy,” said Jakob Dupont, M.D., Head of Global Research & Development at Atara. “Based on the clinical and pre-clinical data generated to date, we remain confident in the potential of ATA2271 and ATA3271 to address patient need in solid tumors and are re-assessing our strategy on how best to generate value from the programs moving forward.”

Upon termination of the agreement in September 2022, the rights and licenses granted by Atara to Bayer under the collaboration will be returned to Atara, and Atara will have full rights to continue the clinical development and future commercialization of its programs worldwide. Atara will continue to support the ongoing ATA2271 Phase 1 study, which is being conducted by Memorial Sloan Kettering Cancer Center (MSK) who has voluntarily paused enrollment of new patients in the study on a temporary basis. Atara and MSK expect to provide a Phase 1 data update for ATA2271 in H2 2022. Atara will also continue to lead IND-enabling studies and process development for ATA3271.