DUBLIN – Opdivo (nivolumab) is now approved in 13 distinct cancer indications spread across eight different types of cancer, but glioblastoma multiforme (GBM) is looking unlikely to become an addition to that list, as Bristol-Myers Squibb Co. reported Tuesday that the PD-1 inhibitor failed to demonstrate a survival benefit in the phase III Checkmate-498 study in 550 newly diagnosed GBM patients. Participants had the difficult-to-treat O6-methylguanine-DNA methyltransferase (MGMT)-unmethylated form of the condition.