Summit Therapeutics (NASDAQ:SMMT) announced a clinical trial collaboration with GSK (NYSE:GSK) to evaluate the combination of ivonescimab, Summit’s novel investigational PD-1/VEGF bispecific antibody, with risvutatug rezetecan (GSK’227), GSK’s investigational B7-H3-targeting antibody-drug conjugate (ADC), in multiple solid tumor settings, including small cell lung cancer (SCLC).
The partnership aims to assess the safety profile and potential anti-tumor activity of the novel combination across various hard-to-treat solid tumors.
Ivonescimab is designed to simultaneously block PD-1-mediated immune checkpoint inhibition and VEGF-driven angiogenesis, while risvutatug rezetecan delivers a potent cytotoxic payload to B7-H3-expressing tumor cells, offering complementary mechanisms that could enhance therapeutic efficacy.
Under the agreement, Summit will supply ivonescimab for the planned study, while GSK will oversee day-to-day clinical operations.
The collaboration is mutually non-exclusive, with each company retaining full rights to their respective investigational products.
Patient dosing is anticipated to commence in mid-2026.
The agreement underscores Summit’s strategy to broaden ivonescimab’s clinical footprint through strategic partnerships, building on its established data in non-small cell lung cancer and other indications, while leveraging GSK’s expertise in ADCs and solid tumor development to explore potentially transformative combination regimens.