AstraZeneca invests $2 billion in Summit Therapeutics

AstraZeneca has agreed to make a $2.0 billion strategic equity investment in Summit Therapeutics. The transaction underpins a collaboration that pairs Summit's flagship bispecific antibody, ivonescimab, with AstraZeneca's oncology pipeline. Following the announcement on Monday, September 28, 2026, Summit shares jumped 15% in extended trading.

Under the deal terms, AstraZeneca will acquire convertible preferred shares at a price equivalent to $18.36 per common share. This represents a 10% premium over Summit's five-day volume-weighted average price. Both drugmakers will evaluate ivonescimab alongside AstraZeneca's sonesitatug vedotin, an investigational antibody-drug conjugate for gastrointestinal cancers.

The companies will share clinical study costs jointly, while AstraZeneca assumes sponsorship duties. Both drugmakers retain full commercial and development rights to their proprietary assets. The partners also signed a non-binding memorandum of understanding to explore combining ivonescimab with additional AstraZeneca treatments, including its broader antibody-drug conjugate portfolio.

The U.S. Food and Drug Administration is reviewing Summit's Biologics License Application for ivonescimab in non-small cell lung cancer, with a target Prescription Drug User Fee Act decision date set for November 14, 2026. The capital support also helps Summit fund late-stage trials in colorectal, head and neck, and bladder cancers.