A systematic literature review of cysteamine bitartrate in the treatment of nephropathic cystinosis.

OBJECTIVES: To summarize available clinical evidence for cysteamine bitartrate preparations in the treatment of nephropathic cystinosis as identified through a systematic literature review (SLR). METHODS: We searched MEDLINE, MEDLINE In-Process and EMBASE using Ovid® with a predefined search strategy through 19(th) January 2016. All publicly available clinical reports on the use of delayed-release (DR) cysteamine bitartrate (PROCYSBI®) or immediate-release (IR) cysteamine bitartrate (Cystagon®) in patients with cystinosis were included. RESULTS: We identified a total of 103 publications and 10 trial records. Of these, 9 studies describe DR cysteamine bitartrate (n = 267 patients), 42 describe IR cysteamine bitartrate (n = 1,427 patients) and in 53 studies the exact preparation was not specified (n = 906 patients). The vast majority of the studies used a non-randomized study design, with randomized clinical trials (RCTs) being scarce (1 study comparing DR and IR formulation) and case reports (n= 49) being the most common study design representing 47% of the total. CONCLUSION: A substantial evidence base for cysteamine bitartrate in the treatment of nephropathic cystinosis was identified. However, the majority of the evidence was of relatively low quality, with evidence levels of 3 or 4.