AstraZeneca strikes clinical collaboration with Summit to test ADC sonesitatug vedotin with ivonescimab in GI cancers

• AstraZeneca agreed to invest USD 2 billion in Summit Therapeutics through newly issued preferred stock convertible to common shares.
• Investment implies rights equivalent to about 12% of Summit’s outstanding common stock, or about 10.6% on a fully diluted basis.
• Separate clinical collaboration will test sonesitatug vedotin, a Claudin-18.2 ADC, combined with Summit’s PD-1/VEGF bispecific ivonescimab in GI cancers.
• Companies will supply their own medicines for combination trials, share trial costs, retain development and commercial rights to their respective products.
• Memorandum of understanding targets a broader global program pairing ivonescimab with AstraZeneca oncology drugs, including additional ADCs.

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