Benzinga | May 17, 2021 08:16AM EDT

Calithera Biosciences and Antengene Enter Worldwide License Agreement for Development & Commercialization of CB-708; Calithera Will Receive An Upfront Payment Of $255M

Calithera Biosciences, Inc. (NASDAQ:CALA), a clinical-stage biotechnology company focused on discovering and developing novel small molecule drugs for the treatment of cancer and other life-threatening diseases, and Antengene Corporation, Ltd. (SEHK: 6996.HK), a leading clinical-stage R&D driven biopharmaceutical company focused on innovative medicines for oncology and other life-threatening diseases, today announced an exclusive, worldwide license agreement for the development and commercialization of CB-708, Calithera's small molecule inhibitor of CD73.

"This agreement validates the capabilities of our drug discovery engine and represents a significant milestone for our CD73 program," said Susan Molineaux, PhD, president and chief executive officer of Calithera. "Antengene brings significant enthusiasm and proven global capabilities to the development and future commercialization of CB-708, a potential best-in-class oral small molecule CD73 inhibitor. This licensing agreement enables the continued advancement of this promising program, while allowing Calithera to focus our resources on our more advanced clinical programs evaluating telaglenastat in non-small cell lung cancer and CB-280 in cystic fibrosis."

CB-708 is a highly potent, selective, orally-bioavailable small molecule inhibitor of CD73. Preclinical data presented at the 2019 American Association for Cancer Research (AACR) Annual Meeting and the 2019 Society for Immunotherapy of Cancer (SITC) Annual Meeting demonstrated that CB-708 has immune-mediated, single agent activity in syngeneic mouse tumor models. In preclinical studies, CB-708 was well-tolerated and showed enhanced anti-tumor activity when combined with either an anti-PD-L1 immunotherapy or with chemotherapeutic agents, such as oxaliplatin or doxorubicin. CB-708 has completed GLP toxicology studies and is poised to advance into clinical development.

"We are excited to continue the advancement of CB-708 through our deep experience in global clinical development and extensive track record in commercialization in major markets around the world," said Dr. Jay Mei, Founder and Chief Executive Officer of Antengene. "CB-708 is a highly differentiated oral small molecule CD73 inhibitor with best-in-class potential. Antengene will continue to complete the GMP manufacturing of CB-708 and advance it into clinical trials for the treatment of multiple cancers including solid tumors and hematologic malignancies. This agreement brings a great addition to our synergistic portfolio of 12 assets with combinatory potential, is a testament to our abilities in accelerating global development, and represents another step in realizing our mission of treating patients beyond borders."

Under the terms of the license agreement, Calithera will receive an upfront payment and potential development, regulatory and sales milestones of up to $255.0 million. Additionally, Calithera is eligible to receive tiered royalties on sales of the licensed product up to low double-digits. Antengene Investment Ltd, a wholly owned subsidiary of Antengene Corporation, will receive exclusive, worldwide rights to develop and commercialize CB-708.