Summit Therapeutics falls after interim results from lung cancer study

Summit Therapeutics

01/05/2026 18:49

** Shares of drug developer Summit Therapeutics SMMT.O fall 23.5% to $16.42

** Summit, late on Thursday, said its combination lung cancer drug, ivonescimab, failed to reach statistical significance in progression-free survival (PFS) in an interim analysis

** Co said threshold to declare statistical significance during the interim analysis was much stricter than it will be at the final planned PFS analysis

** Added an independent data review committee recommended the study continue as planned

** Leerink Partners analyst said the market's negative reaction is "reasonable," adding progression‑free survival benefit looks smaller in the global trial than it did in the earlier China‑only trial

** This will make the combination a less compelling option, "with investors expecting a degradation in benefit from the Chinese to global studies, the bar for excitement is higher"

** Including session moves, stock down 5.5% YTD

(Reporting by Kamal Choudhury and Sneha S K in Bengaluru)

((Kamal.Choudhury@thomsonreuters.com;))