Bayer Terminates $670 Million CAR-T Collaboration with Atara Following Patient Death in Clinical Trial

Compiled by Fan Dongdong

Atara Biotherapeutics had to halt the development of its novel CAR-T therapy two months ago after it led to the death of a patient in the trial. Recently, Bayer, the company's partner, has ultimately decided to terminate their $670 million next-generation mesothelin-directed CAR-T cell therapy collaboration agreement.

At the end of February this year, Atara Biotherapeutics reported that it had voluntarily suspended the recruitment of new patients for its mesothelin-targeted autologous CAR-T therapy. This decision was due to a serious adverse event (SAE) involving a patient's death in the Phase I clinical trial of ATA2271. Atara Biotherapeutics noted that during treatment, the patient had a history of multiple malignancies and other complications, which made the investigation into the cause of the patient’s death more complex.

According to the latest evaluation data released, Bayer has ultimately decided not to further collaborate with Atara Biotherapeutics on the development of mesothelin-targeted CAR-T cell therapy programs, including autologous ATA2271 and allogeneic ATA3271 CAR-T therapies.

The cooperation agreement between the two companies will be officially terminated in September 2022. According to the cooperation agreement, all rights and licenses previously granted to Bayer by Atara Biotherapeutics will be returned to Atara Biotherapeutics. Atara Biotherapeutics will retain full rights to continue global clinical development and future commercialization projects.

Bayer's Decision to Suspend Collaboration Also Forces Atara Biotherapeutics to Make Necessary Adjustments to its CAR-T Therapy Pipeline PlansThe collaboration between the two companies included financial support and the development of ATA3271 (an allogeneic T-cell immunotherapy) and autologous ATA2271 therapy for treating tumors with high mesothelin expression, such as malignant pleural mesothelioma and non-small cell lung cancer.

Among them, the ATA3271 therapy mainly utilizes Atara Biotherapeutics' EBV-T cell platform and is currently undergoing IND (Investigational New Drug) trials. In vitro functional studies have shown that ATA2271 exhibits robust anti-tumor activity after repeated antigen stimulation, with higher amplification levels observed in cells with PD1 DNR compared to CD3z (1XX) CAR-T cells modified alone.

Regarding Bayer's announcement to terminate the collaboration, Pascal Touchon, President and Chief Executive Officer of Atara Biotherapeutics, stated that Atara remains focused on the interim analysis of the Phase 2 EMBOLD study for ATA188, which is expected to be announced in June. He also expressed anticipation for continued progress with tab-cel, including regulatory review by the European EMA and further collaboration with the U.S. FDA on the appropriate BLA pathway.

Touchon pointed out that the company will reassess the strategy for its mesothelin CAR-T development program, thus needing to postpone the anticipated Investigational New Drug (IND) application submission for ATA3271 therapy until after the fourth quarter of 2022. Touchon also stated that the company will maintain its cash runway guidance through the fourth quarter of 2023.

Affected by this unfavorable news, Atara Biotherapeutics, Inc.'s stock fell 15.4% to $4.34 on Thursday evening, and the company's market value has shrunk by nearly 70% year-to-date.

▶Previous related report: "Bayer and Atara Reach Up to $670 Million Collaboration to Co-Develop Cell Immunotherapy》

In December 2020, Bayer reached a collaboration worth up to $670 million with Atara Biotherapeutics, Inc. to jointly develop cellular immunotherapy, primarily involving the collaborative development of CAR-T cell therapy targeting mesothelin for the treatment of solid tumors.

According to the agreement, it mainly includes the development of two candidate drugs: ATA3271, an enhanced allogeneic T-cell immunotherapy, and the autologous drug ATA2271 for treating mesothelin-high tumors such as malignant pleural mesothelioma and non-small cell lung cancer.

According to the terms of the agreement, Atara will lead the new drug research (IND) and process development for ATA3271, while Bayer will be responsible for submitting the new drug application as well as the subsequent clinical development and commercialization. Additionally, Atara will continue to oversee the ongoing Phase I clinical study of ATA2271, for which an IND application has been submitted and the clinical trial has already been initiated.

In terms of payment for the collaboration, Atara will receive a $60 million upfront payment. If Bayer achieves smooth progress in development, regulatory, and commercialization aspects, Atara will be eligible to receive up to $610 million in milestone payments in the later stages, as well as tiered royalties of up to double-digit percentages of net sales.

Reference Source:

1. Bayer sounds retreat from a $670 million CAR-T pact in the wake of a patient death

2. Bayer to end collaboration with Atara Biotherapeutics to develop CAR T-cell therapies

3. Atara Biotherapeutics Provides Update on Strategic Collaboration with Bayer