Ivonescimab Meets OS Endpoint in Keytruda Head-to-Head Trial, but Market Reaction is Muted

Akeso and Summit Therapeutics' ivonescimab has made significant progress in its quest to dethrone Keytruda as a leading cancer immunotherapy. The drug has met its overall survival (OS) endpoint in the Harmoni-2 trial, which evaluated its effectiveness against Merck & Co.'s Keytruda in Chinese patients with first-line PD-L1-positive non-small cell lung cancer.

The statistically significant and clinically meaningful OS improvement for ivonescimab over Keytruda is a crucial milestone for Akeso and Summit. However, the market reaction has been muted, with Akeso's stock price rising only 3.4% in Hong Kong following the announcement.

Analysts are split on the implications of the trial results. While Citi analysts believe that ivonescimab may have offered a life extension benefit stronger than 30%, Evercore analysts suspect that the magnitude could be nearing 30% or even better. Jefferies analyst Faisal Khurshid figures OS 'likely didn't worsen by much (if at all)' across multiple scenarios.

The debate over whether ivonescimab can succeed on a global stage will continue until Summit reads out the results of its global Harmoni-3 trial, which is evaluating the drug's effectiveness in combination with chemotherapy against Keytruda plus chemo. The company has been under pressure after the squamous cohort surprisingly missed statistical significance on progression-free survival (PFS) during an interim analysis.