FDA Approves Cysteamine Ophthalmic Solution for Cystinosis

The US Food and Drug Administration (FDA) has approved cysteamine ophthalmic solution (Cystadrops 0.37%) for treatment of cystinosis manifestations in adults and children.

The cystine-depleting ophthalmic solution has been shown to significantly reduce cystine crystal deposits in the cornea of the eye.

The FDA’s approval of the new treatment, granted to Recordati Rare Diseases Inc., was supported by data from two clinical trials—a Phase 3 open label, randomized, controlled, two-arm multicenter trial and a Phase 1/2a open-label, adaptive dose-response clinical trial.

Across both trials, patients received cysteamine ophthalmic solution at a median frequency of 4 times daily.

In the Phase 3 trial, which included 15 patients receiving the ophthalmic solution, investigators assessed the reduction in corneal cystine crystal density using in vivo confocal microscopy (IVCM). In the investigative treatment group, they saw a 40% reduction in the IVCM total score across all corneal layers from baseline to 90 days.

Results from the Phase 1/2a trial showed that treatment with the solution resulted in a 30% decrease in IVCM total score, which was maintained over the course of the 5-year study period.

The most commonly reported adverse events included eye pain (stinging), blurred vision, eye irritation (burning), eye redness, discomfort at instillation site (sticky eyes or sticky eyelids), eye itching, watery eyes, and medicine deposit on the eye lashes or around the eyes.

"People living with cystinosis and their caregivers have to manage multiple medications every day. To reduce their daily burden, Recordati worked to develop a new viscous eye drop formulation for treating corneal cystine crystals," Andrea Recordati, CEO, Recordati Rare Diseases Inc., said in a statement. "We are pleased to bring Cystadrops to patients in the U.S., the first FDA-approved cysteamine eye drop formulation that reduces corneal crystals with a practical four times a day dosing."