Halitosis in cystinosis patients after administration of immediate-release cysteamine bitartrate compared to delayed-release cysteamine bitartrate

Halitosis due to dimethylsulfide (DMS) generation is a major side effect of cysteamine in the treatment of cystinosis. Recently, an enteric coated formulation of cysteamine bitartrate (RP103) administered twice daily was demonstrated to be non-inferior for lowering WBC cystine levels compared to the non-enteric coated formulation (Cystagon(R)), administered 4 times per day. Since both formulations had different pharmacokinetic profiles, we compared DMS breath levels after administration of either RP103 or Cystagon(R) in four cystinosis patients. Although cysteamine areas under the curve (AUCs) were comparable, AUC of DMS was lower after the administration of RP103 compared to Cystagon(R). This observation is of importance in cystinosis patients, since halitosis hampers compliance with cysteamine therapy. (C) 2012 Elsevier Inc. All rights reserved