GO! Astellas picks up partner in convertibleCAR for backloaded $780M antibody project

Astellas has floored the accelerator on an immuno-oncology R&D project, putting down $20.5 million to team up with GO Therapeutics in a race to find antibodies with high affinity to two different glycoprotein targets.

The strategic research collaboration and license agreement is between Xyphos Biosciences, which sold up to Astellas for $120 million upfront late in 2019, and GO. Xyphos is a West Coast biotech that is built on a technology for controlling cell therapies. The resulting convertibleCAR cells have modified NKG2D receptors designed to enable physicians to control their activity using engineered molecules such as bispecific antibodies.  

Under the terms of the deal with GO, the parties will collaborate on the identification of antibodies for two targets. GO will lead the discovery of antibodies against the targets, leveraging its expertise in cancer O-glycoproteins. Astellas will handle research activities, clinical development and beyond. The plan is to apply the antibodies to a range of therapeutic modalities. 

“The combination of GO's targets and antibodies and Astellas' ACCEL technology promises to create a new generation of cancer treatments that have a greater therapeutic index. This will enable oncologists to increase the efficacy of antibody-based immunotherapies for solid tumors with less damage to healthy tissues,” Constantine Theodoropulos, co-founder and CEO of GO, said in a statement.

Astellas is paying GO $20.5 million upfront to enter into the deal. Beyond that, GO could receive up to $763 million in milestone and contingency payments as the antibodies discovered in the collaboration advance. 

The figures make the deal potentially significant for both parties. The single-target deal GO landed with Roche in 2018 was worth $9 million in upfront and near-term milestones, plus $186 million in potential paydays down the line. Astellas snapped up the preclinical Xyphos, which lists a CD20 convertibleCAR-T as its most advanced candidate, for $120 million upfront and up to $545 million in milestones.