Shares in late morning were trading at $61.36, up 1.3%. The stock is up 9.1% in 2018 and down 6.3% over the past 12 months.
"The Keynote-407 data was a clear positive and even better than we had expected in the squamous lung cancer population," Credit Suisse Securities (USA) LLC analyst Vamil Divan wrote in a note on Sunday.
Keynote-407 is a Phase 3 study of Keytruda in tandem with carboplatin-paclitaxel or nab-paclitaxel as a first-line treatment for a type of lung cancer. Kenilworth, N.J.-based Merck said Sunday that the combination treatment showed improved overall survival regardless of programmed death-ligand 1 (PD-L1) expression. PD-L1 is a form of protein that appears to affect the immune system.
Merck also presented, among others, data from Keynote-042, its Phase 3 clinical trial of Keytruda as a monotherapy for the first-line treatment of patients with locally advanced or metastatic non-small cell lung cancer whose tumors expressed PD-L1. The study showed Keytruda resulted in longer overall survival compared with platinum-based chemotherapy.
"Keynote-042 was maybe not quite the knockout punch that it could have been, but MRK is in a very dominant position in lung cancer, with expansion into other indications ongoing," Divan wrote.
ASCO's annual meeting kicked off Friday and will wrap up Tuesday.
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