Astellas Acquires Xyphos Biosciences for $665 M

By Emily Forster -

January 2, 2020

Astellas Pharma has acquired Xyphos Biosciences, a South San Francisco, California-based company specializing in immuno-oncology products, for $120 million upfront and future development milestones for a total transaction value of $665 million.

With the acquisition, Astellas will gain Xyphos’ proprietary ACCEL (Advanced Cellular Control through Engineered Ligands) technology platform as well as immuno-oncology talent. Xyphos has developed a synthetic biology platform to direct cells of the immune system to target single or multiple tumor antigens while controlling the immune-cell proliferation and endurance, according to information from the companies. The proprietary technology enables the exclusive or preferred delivery of various classes of single or multiple targeting and modulating agents, including bispecific antibodies, cytokines and kill functions.

Xyphos’ proprietary molecules can be delivered to natural immune cells or to engineered chimeric antigen receptor (CAR) cells to generate immunotherapies for oncology. Xyphos’ patented CAR technology is based on an engineered modification to a natural human receptor named NKG2D. NKG2D exists on natural killer (NK) cells and some T-cells. The designed modification of NKG2D renders it inert, that is, unable to bind to any of its natural ligands, which occur on stressed cells. Through further protein engineering, several natural ligands of NKG2D have been modified to bind exclusively to the otherwise inert NKG2D receptor. Various functional molecules (for example, antibodies that recognize specific tumor antigens) are attached to the modified ligand. The ligand-directed functional molecules then bind exclusively to immune cells expressing the inert CAR on their surface – the proprietary convertible CAR-cells. The CAR-cells can be directed by the ligand-bound antibody to seek, become activated, and attack a targeted cancer cell. Xyphos' first convertible CAR-T cell product candidate is in preclinical development and is scheduled to be tested in a first-in-human clinical study in 2021.

Considering the acquisition, $120 million was paid upon closing of the acquisition, and Xyphos became a wholly owned subsidiary of Astellas. In addition to this payment and potential future development milestone payments, the total transaction value is $665 million.

Source: Astellas Pharma and Xyphos Biosciences