AstraZeneca announced a $2 billion equity investment in Summit Therapeutics centered on ivonescimab, a PD-1/VEGF bispecific, as the companies move to build combination trials pairing the agent with AstraZeneca’s antibody-drug conjugates. Under the deal terms, AstraZeneca plans to purchase approximately 109,000 shares of convertible preferred stock, translating into a 12% stake in Summit’s outstanding common stock (10.6% on a fully diluted basis). The partners also outlined a clinical collaboration to evaluate ivonescimab alongside AstraZeneca assets, including sonesitatug vedotin (sone-ve) and other ADCs, with a first wave anticipated in gastrointestinal cancers. AstraZeneca’s positioning reflects a strategy to broaden immunotherapy reach by integrating bispecifics with targeted cytotoxic payloads, while leveraging early positive clinical signals that Summit and AstraZeneca have reported separately for ivonescimab and sone-ve. For Summit, the investment provides additional resourcing while AstraZeneca’s involvement expands the probability of additional combination programs across multiple tumor types.