Rigel’s 2nd PhIII for fostamatinib scuttled by a single placebo response, shares crater
Rigel Pharmaceuticals continues to be plagued by a low response rate in its big Phase III program for fostamatinib. But unlike its first late-stage data drop, which scored a hit on the primary endpoint, the biotech now has to explain why its second confirmatory study failed.
It’s not an enviable task. At the end of August the South San Francisco-based biotech’s share price $RIGL went on a roller coaster ride with a positive but unimpressive 18% response rate for immune thrombocytopenia patients who achieved a stable platelet response. That was exactly the same rate seen in the second Phase III, only this time one patient on a placebo also achieved a stable platelet response, and that scuttled any shot at hitting the primary endpoint. For analysts who had been looking for a response rate at least in the low 20s with clear signs of efficacy, this stumble will not play well.
Unlock this article instantly by becoming a free subscriber.
You’ll get access to free articles each month, plus you can customize what newsletters get delivered to your inbox each week, including breaking news.