iTeos Therapeutics, GSK Enter Monoclonal Antibody Alliance

iTeos Therapeutics and GlaxoSmithKline plc entered an agreement to co-develop and co-commercialize EOS-448, an anti-TIGIT monoclonal antibody currently in phase I development as a potential treatment for cancer. TIGIT, part of the CD226 checkpoint axis, has demonstrated potential as a promising target for the next generation of immuno-oncology therapies based on preclinical data and a phase II randomized clinical trial. With this collaboration has access to antibodies that synergistically target all three known CD226 checkpoints, TIGIT, CD96 and PVRIG.

iTeos will receive $625 million upfront and will be eligible to receive up to an additional $1.45 billion in milestones, based on certain development and commercial milestones.
GSK and iTeos will share responsibility and costs for the global development of EOS-448 and will jointly commercialize and split profits in the U.S. Outside of the U.S., GSK will receive an exclusive license for commercialization and iTeos will receive tiered royalty payments.

Since GSK validated the role of CD226 axis targets as important in oncology, it has been strategically building a carefully constructed set of assets to target this network of checkpoint inhibitors. The addition of EOS-448 results in GSK being the only company with antibodies targeting all three known checkpoints – TIGIT (via EOS-448), CD96 (via GSK’608), and PVRIG (via GSK’562). Together with GSK’s recently approved anti-PD-1, Jemperli (dostarlimab), this portfolio of potential next gen immuno-oncology agents will be explored through various novel combinations, including doublets and triplets, to evaluate their potential in multiple different cancers.

EOS-448 is currently in an open-label phase I study in patients with advanced solid tumors. GSK and iTeos plan to start combination studies of EOS-448 with dostarlimab in 2022. GSK’608 (anti-CD96 being developed in collaboration with 23andMe) is in phase I as monotherapy and in combination with dostarlimab. GSK expects to submit an Investigational New Drug application for GSK’562 (anti-PVRIG in-licensed as SRF-813 from Surface Oncology) by mid-2022.