Bristol-Myers: 2 immunotherapy drugs up survival over 1 in melanoma, but worsen side effects

A study shows giving advanced melanoma patients two new Bristol-Myers drugs together held the deadly skin cancer at bay far longer than just one.

However, the combo sharply increased serious side effects, leading more patients to drop out.

The study of 142 patients not treated previously found combining Yervoy and Opdivo reduced chances of death or cancer progressing by 60 percent over Yervoy alone. In the Yervoy-only group, death or worsening of cancer occurred after 4 1/2 months on average. That average hasn't been determined yet in the combo group, where some patients remained in treatment at 15 months.

Tumors were eliminated in 22 percent of those getting both medicines but in none receiving only Yervoy.

The study was presented at the American Association for Cancer Research conference in Philadelphia.