The US Food and Drug Administration has granted priority review designation to crofelemer, an experimental treatment for HIV-associated diarrhea, the manufacturer Salix Pharmaceuticals Ltd. reported. Priority review status means the agency aims to complete its analysis of the application within six months, rather than the customary 10 months; FDA has set an action date of June 5 for the application. Salix -- based in Raleigh, N.C. -- holds North American and European rights to the drug; it has a supply agreement with India's Glenmark Pharmaceuticals Ltd.