Merck and Moderna’s success with a personalized cancer vaccine designed to keep melanoma at bay opens a new avenue of treatment that doctors hope will work against many types of tumors.

News of first positive large late-stage trial result for drug could signal new era for treating solid-tumor cancers, with tests underway for lung, breast and pancreatic cancers

At an interim data check, investigators of a key trial found the individualized mRNA treatment kept disease from returning and stopped its spread, sparking a surge in Moderna…