Zynerba's ZYN002 misses in Phase II for OA

Zynerba Pharmaceuticals Inc. (NASDAQ:ZYNE) reported top-line data from the Phase II STOP trial in 320 patients with osteoarthritis (OA) of the knee showing that once-daily 250 and 500 mg doses of ZYN002 each missed the primary endpoint of reducing the weekly mean of the 24-hour average worst pain score from baseline to week 12 vs. placebo (2.64 and 2.83 points, respectively, vs. 2.37 points). Low-dose ZYN002 met the secondary endpoint of improving a composite responder analysis, defined as achieving a ≥30% reduction in average worst daily pain score and a ≥20% improvement in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function score, vs. placebo (p=0.016). Additionally, a significantly greater proportion of patients who received low-dose ZYN002 achieved a ≥30% reduction in worst pain severity at week 8 vs. placebo (p=0.037). ZYN002 was well tolerated.

Despite the miss, Zynerba said it plans to continue development of ZYN002 in OA, with a Phase III program slated to start next year. On a conference call to discuss the data, CEO Armando Anido said the company believes "the totality of the data from the trial provides us with confidence that ZYN002 shows promise for the treatment of OA and there is a path forward in the pivotal studies." Zynerba said it plans to recommend to FDA that the composite responder analysis endpoint be the primary endpoint in the Phase III program...