The U.S. Food and Drug Administration has approved a drug to treat nephropathic cystinosis. The drug, Procysbi, is made by Raptor Pharmaceutical Corp.

Diagnosed at infancy, cystinosis is marked by the inability to metabolize cystine. Accumulation of cystine is toxic to cells leading to kidney failure, muscle wasting and premature death.

Procysbi is a delayed-release formulation of cysteamine bitartrate, a drug sold under the brand name Cystagon by Mylan Inc. The drugs work by lowering cystine levels. Procysbi is designed to be given once every 12 hours, instead of once every six hours for Cystagon.