Clinical safety and efficacy of CYSTADROPS were assessed in two studies: a single-arm study conducted for 5 years (OCT-1) and a randomized controlled study conducted for 90 days (CHOC).
In the OCT-1 study, 8 patients with cystinosis (2 males and 6 females) with a mean age of 12.1 ± 4.6 (range: 7.0 – 21.0) were enrolled and received a median of 4 drops/eye/day of CYSTADROPS. In CHOC study, 32 patients with cystinosis (15 males and 17 females) with a mean age of 17.1 ± 13.0 (range: 2.9 – 62.6) were enrolled and received a median of 4 drops/eye/day. Fifteen patients were exposed to CYSTADROPS and 16 were exposed to cysteamine hydrochloride 0.1% (control arm).
Efficacy was assessed with In-Vivo Confocal Microscopy total score (IVCM score) by quantifying the cystine crystals in the cornea. A decrease in IVCM total score from baseline indicated a reduction in corneal crystals.
In the CHOC study, after 30 and 90 days of treatment with CYSTADROPS, 12% and 40% reduction in the total IVCM total score across all corneal layers was observed from baseline, respectively. CYSTADROPS demonstrated greater reduction compared to the control arm at 90 days. The average reduction in IVCM total score was 4.6 in the CYSTADROPS arm and 0.5 in the control arm, mean difference 3.8 (95% CI: (2.1, 5.6)).
In the OCT-1 study, a mean decrease in corneal cystine crystal deposits of 30%, in comparison with baseline, was maintained over the 60 month period of the study.
