A phase III trial testing a combination of Bristol-Myers Squibb Co.'s Opdivo (nivolumab) and Yervoy (ipilimumab) as maintenance therapy in some patients with extensive-stage small-cell lung cancer (SCLC) found it failed to improve overall survival vs. placebo. Results of the study, called Checkmate-451, together with Opdivo's recent failure to beat chemotherapy's OS benefit in relapsed SCLC during the confirmatory Checkmate-331 trial could put its accelerated approval in SCLC in jeopardy, Evercore ISI analyst Umer Raffat said.