The present study is a randomized double masked clinical trial consisting of two parts. The first part is a safety study utilizing patients with cystinosis who have been on bilateral treatment successfully. They now have one eye randomzied to the old cysteamine preparation and the other eye to the NDA formulation. The second part is an efficacy study enrolling patients who have never received treatment for their corneal cystine crystals. The eyes are randomly assigned to cysteamine eye drops in one eye and the NDA formulation in the other eye.
