Ariad plunges on Iclusig hold

Ariad Pharmaceuticals Inc. (NASDAQ:ARIA) plummeted $11.31 (66%) to $5.83 on Wednesday after FDA placed a partial clinical hold halting enrollment in all trials of Iclusig ponatinib, including the confirmatory Phase III EPIC trial evaluating the leukemia drug in newly diagnosed patients. The hold came after two-year follow-up data from the pivotal Phase II PACE trial showed an increase in treatment-emergent serious arterial thrombotic events with longer use of Iclusig.

Last December, FDA granted accelerated approval to Iclusig for chronic myelogenous leukemia (CML) and Philadelphia-chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) based on PACE data, which evaluated the drug in heavily pretreated patients. Iclusig's label -- which has a boxed warning about the risk of arterial thrombosis and liver toxicity -- notes that 45 mg once-daily Iclusig led to treatment-emergent serious arterial thrombotic events in 8% of patients after 11 months of follow up in the trial. The updated data collected at a median follow-up of 24 months show Iclusig led to arterial thrombotic events in 11.8% of patients. Ariad said it is working with FDA to add the 24-month data to Iclusig's label (see BioCentury, Dec. 24, 2012). ...