FDA approves Gilead's idelalisib

FDA approved Zydelig idelalisib from Gilead Sciences Inc. (NASDAQ:GILD) on Wednesday for three blood cancers. The agency granted full approval to Zydelig in combination with rituximab to treat relapsed chronic lymphocytic leukemia (CLL), for which the compound has breakthrough therapy designation. FDA granted accelerated approval to the small molecule inhibitor of phosphoinositide 3-kinase (PI3K) delta as monotherapy to treat relapsed follicular B cell non-Hodgkin's lymphoma (FL) and relapsed small lymphocytic lymphoma (SLL) -- both types of indolent NHL. The accelerated approvals are based on the single-arm Phase II Study 101-09, where Zydelig led to an overall response rate (ORR) of 54% in 72 FL patients and 58% in 26 SLL patients (see BioCentury Extra, Dec. 9, 2013).

Zydelig's label includes a boxed warning on the risk of fatal and serious toxicities, including liver toxicity, diarrhea, colon and lung inflammation and intestinal perforation. The drug was also approved with a REMS that includes a communication plan. Gilead said it plans to launch the drug in the U.S. as soon as possible with a wholesale acquisition cost of $7,200 for a one-month supply. According to Zydelig's label, in clinical trials the median duration of exposure to Zydelig was five months in CLL patients and 6.1 months in indolent NHL patients. ...