Pointing to an anomalously high placebo response rate at eastern European trial sites in its Forward phase III trial testing fostamatinib in warm autoimmune hemolytic anemia (wAIHA), Rigel Pharmaceuticals Inc. executives remained confident there could be a path forward for the SYK inhibitor in treating the rare blood disorder. The disappointing top-line data, however, sent company shares (NASDAQ:RIGL) falling more than 60% June 8 to close at 70 cents, a penny above its same day 52-week low.