Long-Term Safety Follow-up Study of Cysteamine Bitartrate Delayed-release Capsules (RP103)

Inclusion Criteria: * Male and female subjects must have completed the last visit of Study RP103-03 and be willing to continue with RP103 treatment. OR for patients who did not complete the RP103-03 study: * Male and female subjects must have cystinosis. * Subjects must be on a stable dose of Cystagon® at least 21 days prior to Screening. * Within the last 6 months, no clinically significant change from normal in liver function tests (i.e., alanine aminotransferase \[ALT\], aspartate aminotransferase \[AST\], total bilirubin) and renal function (i.e., estimated glomerular filtration rate \[eGFR\]) at Screening as determined by the Investigator. * Subjects with an eGFR corrected for body surface area \> 30 mL/min/1.73m². * Sexually active female subjects of childbearing potential (i.e., not surgically sterile \[tubal ligation, hysterectomy, or bilateral oophorectomy\] or at least 2 years naturally postmenopausal) must agree to utilize the same acceptable form of contraception from Screening through completion of the study. * Subjects must be willing and able to comply with the study restrictions and requirements. * Subjects or their parent or guardian must provide written informed consent and assent (where applicable) prior to participation in the study. Exclusion Criteria: * Patients enrolled in the previous Study RP103-03 who did not complete their last scheduled Study visit or who do not wish to continue on treatment with RP103. AND for patients who did not complete the RP103-03 study: * Subjects less than 1 year old * Subjects with a known history, currently of the following conditions or other health issues that make it, in the opinion of the investigator, unsafe for them to participate: inflammatory bowel disease (if currently active) or have had prior resection of small intestine; Heart disease (e.g., myocardial infarction, heart failure, unstable arrhythmias or poorly controlled hypertension) 90 days prior to Screening; Active bleeding disorder 90 days prior to Screening; Malignant disease within the last 2 years. * Patients with a hemoglobin level \< 10 g/dL at Screening or a level that, in the opinion of the investigator, makes it unsafe for the subject to participate. * Subjects with known hypersensitivity to cysteamine or penicillamine. * Female subjects who are nursing, planning a pregnancy, known or suspected to be pregnant, or have a positive serum pregnancy screen. * Subjects who, in the opinion of the Investigator, are not able or willing to comply with the protocol.