Astellas and Ambrx Collaborate on Antibody Drug Conjugates for Oncology

Astellas and Ambrx have entered into a collaboration to discover and develop novel antibody drug conjugates (ADCs) for an undisclosed number of targets in oncology. ADCs enable targeted delivery of drugs to the target tissue.

Ambrx will use its site-specific conjugation technology along with proprietary linkers and payloads to produce optimized ADCs. “Agensys, Inc., an affiliate of Astellas which specializes in therapeutic antibody research and development in cancer, has significant experience with ADCs as oncology therapeutics and is looking to further expand its capabilities in this area. Ambrx offers a novel approach to allow creation of site-specific and highly stable conjugations that have the potential to further optimize drug delivery to tumor cells.” said David Stover, senior vice president and head of the Agensys site, in a press statement. Ambrx ADCs have preclinically demonstrated high potency and a wider therapeutic index than ADCs created using conventional non-specific conjugation.

Lawson Macartney, chief executive officer of Ambrx, said “We recognize Astellas as a leader in the development of innovative therapeutics for oncology and are proud to initiate this collaboration. We look forward to developing these therapeutics while also advancing our broad pipeline of partnered and wholly owned therapeutic candidates with best-in-class conjugation.”

Under the terms of the agreement, Ambrx will receive an upfront payment of $15 million from Astellas. Ambrx is also eligible for up to $285 million in potential R&D as well as regulatory- and sales-based milestones. A portion of these milestones, in addition to royalties on any net sales, will be contingent on eventual successful commercialization of products developed as a result of this partnership. Astellas will receive worldwide rights to develop and commercialize ADCs for oncology. Other terms of the collaboration have not been disclosed at this time.