By Colin Kellaher 



  Merck & Co. on Wednesday said its cancer drug Keytruda met its primary endpoints in a Phase 3 study in esophageal cancer. 


  The Kenilworth, N.J., drug maker said Keytruda in combination with chemotherapy showed a statistically significant and clinically meaningful improvement in overall survival and progression-free survival versus chemotherapy alone as the first-line treatment of patients with locally advanced or metastatic esophageal cancer. 


  Merck said the study also met the key secondary endpoint of objective response rate, adding that Keytruda's safety profile was consistent with that observed in previously studies. 


  Keytruda, a cancer drug that harnesses a patient's immune system to fight tumors, has been approved in several indications in numerous cancers. 


  Write to Colin Kellaher at colin.kellaher@wsj.com