AstraZeneca (LON: AZN) shares rose about 2.1% in early London trade after the drugmaker announced a $2bn equity investment in Summit Therapeutics and a deal to test a combination of their cancer drugs. The company announced the deal at 7am, before the market opened.
The shares opened at 12,526p and were at 12,757p by 9.07am, in a delayed quote, against yesterday’s close of 12,492p. The day’s range so far runs from 12,512p to 12,788p.
The deal pairs AstraZeneca’s Sone-Ve, an antibody-drug conjugate (ADC) that targets a protein called Claudin-18.2, with Summit’s ivonescimab, a PD-1/VEGF bispecific, meaning one drug that hits two targets. Sone-Ve has produced positive results in gastric cancer, with a statistically significant improvement in overall survival, in the CLARITY-Gastric01 trial, which will be presented at the ESMO 2026 Presidential Symposium.
Trials in gastrointestinal cancers are due to start imminently, with each company supplying its own medicine and sharing the trial costs. A memorandum of understanding also points to a wider global programme combining ivonescimab with more AstraZeneca ADCs.
Susan Galbraith, AstraZeneca’s Executive Vice President for Oncology Haematology R&D, framed it as part of the company’s oncology strategy.
A core pillar of our oncology strategy is to broaden the reach of our ADC portfolio as the backbone of treatment across tumour types with combinations alongside next-generation immunotherapies.
Susan Galbraith, AstraZeneca
The $2bn buys newly issued equity equal to about 12.0% of Summit’s common stock, or 10.6% fully diluted, including roughly 109 thousand preferred shares convertible at 1,000 common shares each. Conversion is subject to regulatory clearances, and closing is expected within a week.
Each company keeps its own rights to its medicine. Dr Maky Zanganeh, Summit’s President and Co-CEO, said the developments open an exciting new chapter for ivonescimab.
The rise coincides with the announcement, but nothing confirms it was the cause. Today’s price is still about 18% below the February closing high of 15,542p.
The shares are down 7.5% this year from 13,790p at the end of 2025, though up about 15% on a year ago.