(Reuters) - Ariad Pharmaceuticals Inc stopped the most advanced trial of one of its cancer drugs after some patients developed blood clots in their arteries, sending its shares down 38 percent before the bell.
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Seven other trials of the drug, Iclusig, will continue after the halt of the late-stage trial for patients suffering from newly diagnosed chronic myeloid leukemia, a form of blood cancer.
Ariad shares have lost three-quarters of their value in the two weeks since the U.S. Food and Drug Administration placed a partial hold on new enrollments for all trials testing the drug.
The company said on Friday it had come to an agreement with the FDA that the trial should be terminated.
The FDA said last week it was investigating a number of reports of serious and life-threatening adverse events in patients taking the drug.
Iclusig was approved by the FDA in December to treat two types of rare blood cancer, but the regulator required that the drug carry a warning of the potential for blood clots in the arteries and liver toxicity.
(Reporting By Vrinda Manocha in Bangalore; Editing by Rodney Joyce, Maju Samuel)
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