Safety/Effectiveness Study of Cysteamine Bitartrate Delayed-release Capsules (RP103) in Cysteamine Treatment Naive Patients With Cystinosis

Inclusion Criteria: * Male or female with a documented diagnosis of cystinosis * No clinically significant change in liver function tests, i.e. 1.5 times upper limit of normal (ULN) for alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and/or 1.5 times ULN for total bilirubin, within 6 months prior to Screening * No clinically significant change in renal function, i.e. estimated glomerular filtration rate (GFR) within 6 months prior to Screening * Must have an estimated GFR \> 20 mL/minute/1.73m² (using the equation from Schwartz 2009 J Am Soc Nephrol 20:629-647) * Female participants who are sexually active and of childbearing potential, i.e. not surgically sterile (tubal ligation, bilateral oophorectomy, or hysterectomy) or at least 2 years naturally postmenopausal must agree to use an acceptable form of contraception from Screening through completion of the study. Acceptable forms of contraception for this study include hormonal contraceptives (oral, implant, transdermal patch, or injection) at a stable dose for at least 3 months prior to Screening, barrier (spermicidal condom or diaphragm with spermicide), IUD, or a partner who has been vasectomized for at least 6 months. Childbearing potential was defined as a female who had reached menarche. * Participant or their parent or guardian must provide written informed consent and assent (where applicable) prior to participation in the study * Had not taken any form of cysteamine bitartrate in the past Exc…