Bristol-Myers Drug Study Halted Early for Benefit

Bristol-Myers Squibb Co. (BMY) said a Phase 3 study of its nivolumab treatment for melanoma was stopped early after an analysis by an independent Data Monitoring Committee showed evidence of superior overall survival compared with another therapy.

Nivolumab is designed to target an immune-cell pathway known as PD-1 ("programmed death receptor 1"), which acts as a brake on the immune system to prevent it from attacking healthy cells. Cancer cells can exploit the mechanism by latching on and using PD-1 to escape destruction by the body's immune system. By blocking the interaction, nivolumab allows the immune system to attack cancer cells.

Bristol-Myers, Merck & Co., Roche Holding AG and other companies are racing to bring new immunotherapy drugs to what analysts predict will be a multibillion-dollar market.

Bristol Myers shares rose 2.6% to $49.55 in recent after-hours trading.

--Peter Loftus and Ron Winslow contributed to this article.

Write to Tess Stynes at [e-mail]

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