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Prescribing Information


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How Does CYSTARAN Work?

Cysteamine acts as a cystine-depleting agent. It enters the cystinotic lysosome and reacts with the cystine. The result is cysteine and cysteine-cysteamine mixed disulfides. These molecules are able to exit the lysosome via a transport system. This ultimately results in reduction of the corneal cystine crystals.1-3

CYSTARAN reduces corneal cystine crystals

Cystine crystals within the cornea viewed with slit-lamp photography4


This patient was aged 5 years 9 months at the start of treatment.

Please see the CYSTARAN Prescribing Information for more information.


References: 1. CYSTARAN [prescribing information]. Gaithersburg, MD: Leadiant Biosciences, Inc.; 2012. 2. Cystinosis Research Network Web site. Cystinosis symptoms & treatment. Available at: Accessed March 13, 2013. 3. Elenberg E. eMedicine Pediatrics: General Medicine Web site. Cystinosis. Available at: Accessed March 13, 2013. 4. Gahl WA, Kuehl EM, Iwata F, Lindblad A, Kaiser-Kupfer MI. Corneal crystals in nephropathic cystinosis: natural history and treatment with cysteamine eyedrops. Mol Genet Metab. 2000;71:100-120.



CYSTARAN is a cystine-depleting agent indicated for the treatment of corneal cystine crystal accumulation in patients with cystinosis.

Important Safety Information:

The most frequently reported ocular adverse reactions occurring in ≥10% of patients were sensitivity to light, redness, eye pain/irritation, headache, and visual field defects.