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

This is a long-term, open-label, study to determine the safety and tolerability of twice a
day treatment with cysteamine bitartrate delayed-release capsules (RP103). It will involve
6-9 monthly clinic visits followed by quarterly clinic visits for the duration of the study
and home use of cysteamine bitartrate delayed-release capsules.

Initially, enrollment was open to those patients who had completed the previous Phase 3 Study
(RP103-03, NCT01000961). Subsequently enrollment in Study RP103-04 was opened to additional
participants, including children aged 1 to 6 years and renal transplant recipients, who had
previously been on a stable dose of Cystagon® for at least 21 days.

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.