Fasinumab, the nerve growth factor (NGF) receptor antagonist that Regeneron Pharmaceuticals Inc. is advancing with partner Teva Pharmaceutical Industries Ltd., passed its efficacy test for the treatment of chronic pain from osteoarthritis (OA) of the knee and hip, based on findings from a substudy of a larger, long-term phase III study. However, two higher-dose regimens – 3 mg every four weeks and 6 mg every eight weeks – were discontinued earlier this year at the behest of an independent data monitoring committee. And the waiting continues for top-line safety data.