Bristol immunotherapy prolongs survival in melanoma trial

(Reuters) - A late stage trial testing Bristol-Myers Squibb Co's cancer immunotherapy nivolumab in advanced melanoma patients was halted early after it was determined that the drug was likely to prolong survival, the company said on Tuesday. The 418-patient Phase III study, called CheckMate -066, was testing nivolumab as an initial, or first line, therapy for patients with advanced melanoma, the deadliest form of skin cancer. An interim analysis performed by an independent data monitoring committee found evidence of superior overall survival in patients receiving nivolumab compared with those who received the chemotherapy dacarbazine, Bristol said. The committee stopped the study early to allow the dacarbazine patients to switch to the Bristol drug. Nivolumab belongs to a new class of medicines called PD-1 inhibitors that have generated great excitement for their ability to help the immune system recognize and attack cancer. Analysts have forecast multibillion-dollar sales for the drugs being developed by several companies once they gain regulatory approval. "The outcome of CheckMate -066 ... represents the first well-controlled, randomized Phase III trial of an investigational PD-1 checkpoint inhibitor to demonstrate an overall survival benefit," Michael Giordano, Bristol's head of oncology development, said in a statement. Independent monitors routinely analyze data from blinded trials at various points and can stop a study if a safety problem arises or if the study drug is seen as likely to prove clearly superior to the control medicine. (Reporting by Bill Berkrot; Editing by Steve Orlofsky)