Italian pharmaceutical company Recordati has received US Food and drug Administration (FDA) approval for its eye drop, Cystadrops, for treating cystinosis-related corneal crystal deposits.
Cystinosis is a rare genetic disorder causing an accumulation of amino acid cystine within cells. These form crystals which can build up and damage cells, negatively affecting many systems in the body, especially the kidneys and eyes.
Cystadrops, (cysteamine ophthalmic solution 0.37%), a viscous eye drop solution was shown to significantly reduce cystine crystal deposits in the cornea of the eye in two company trials. In both, patients received Cystadrops at a median frequency of four times per day. The phase III open-label, randomised, controlled, two-arm multicentre trial (n=15 in the Cystadrops arm). Using in vivo confocal microscopy (IVCM), resulted in a 40% reduction in corneal cystine crystal density across all corneal layers from baseline to 90 days. While the other, phase I/IIa open-label, adaptive dose-response clinical trial of eight cystinosis patients, resulted in a 30% decrease, which was sustained for five years.
Common adverse reactions, however, included eye pain, irritation, redness, itching, blurred vision, sticky eyes/eyelids at the instillation site, watery eyes and/or medicine deposits on eye lashes or around the eyes.
Cystadrops was approved in Europe in 2017 but was declined by Pharmac in New Zealand in 2019 due to “low quality evidence of benefit and the high proposed cost of Cystadrops compared with the current standard of care.”