FDA panel votes against Xinlay

FDA's Oncologic Drugs Advisory Committee voted 13-0 against recommending approval of Xinlay atrasentan from Abbott (ABT) to treat patients with metastatic hormone-refractory prostate cancer with bone metastases. The bone metastases group was a retrospectively defined subset that showed a significant increase in time to progression (TTP) in ABT's Phase III trial. But because the study did not show a significant TTP increase in the overall population -- the primary endpoint -- the panelists unanimously agreed that the subgroup results were not statistically persuasive. "The study is a failure for the primary endpoint they had," said panel member Ralph D'Agostino, a professor of mathematics and statistics at Boston University. "The lack of significance ends the discussion. Are the other numbers meaningful? No." ...