Endocyte Inc.'s vintafolide-induced roller coaster ride continued Friday. A month after shares jumped a whopping 92 percent on a positive opinion from European regulators on conditional approval of the drug and its companion imaging agents in ovarian cancer, shares of the West Lafayette, Ind.-based company took a 62 percent tumble on news that the phase III ovarian cancer trial was halted for futility, likely putting the kibosh on that expected EU launch.