(Reuters) -AstraZeneca is in talks with Summit Therapeutics to license an experimental lung-cancer drug under a deal worth as much as $15 billion, Bloomberg News reported on Thursday, citing people familiar with the matter.

Shares of Summit Therapeutics surged 9.7% to $25.81 in morning trade.

The Menlo Park, California-based drug developer did not immediately respond to Reuters' request seeking comment, while an AstraZeneca spokesperson declined to comment.

A deal could include an upfront payment of several billion dollars to Summit, besides milestone payments later on, Bloomberg News said. The talks could still fall apart or Summit could opt for a different partner for licensing, according to the report.

The negotiations involve ivonescimab, a drug Summit secured rights for through a separate deal worth up to $5 billion with China-based Akeso in December 2022.

Summit is testing ivonescimab to treat patients with a type of lung cancer who have received prior treatment. The drug has already been approved in China in May last year, and Summit plans to file for marketing approval in the United States.

In a late-stage study, ivonescimab, in combination with chemotherapy, showed a positive trend in overall survival, but "without achieving a statistically significant benefit," the company said in May.

An earlier data last year had shown some lung cancer patients having better survival rates on the drug than those on Merck's blockbuster Keytruda.

Summit and Akeso were testing ivonescimab-chemotherapy regime in a study conducted in China, against BeiGene's approved drug Tevimbra in combination with chemotherapy.

(Reporting by Siddhi Mahatole in Bengaluru; Editing by Shailesh Kuber and Leroy Leo)