SRF813 is a fully human immunoglobulin G (IgG1) antibody targeting poliovirus receptor-related immunoglobulin domain-containing (PVRIG), an inhibitory protein expressed on natural killer (NK) cells and T cells. SRF813 binds to a distinct epitope on PVRIG and blocks the interaction of the protein with CD112, which is overexpressed in tumor cells.

In preclinical studies, the candidate promotes activation of both NK cells and T cells and has the potential to elicit strong antitumor responses and immunological memory. SRF813 is currently being evaluated in studies to support an investigational new drug (IND) application with an IND submission planned for 2021.

Under the agreement, GSK will make an $85 million upfront payment to Surface Oncology. In addition, Surface Oncology may receive up to an additional $730 million in future milestone payments, as well as be eligible to receive tiered royalties on global net sales.