Phase 3 Study of Cysteamine Bitartrate Delayed-release (RP103) Compared to Cystagon® in Patients With Cystinosis
Condition: Cystinosis
MeSH terms: Cystinosis
Intervention: Cystagon® (Cysteamine Bitartrate); Cysteamine Bitartrate Delayed-release Capsules (RP103)
Intervention description: Run-in Period (Weeks 1, 2, 3) and Period 1 (Weeks 4, 5, 6) or Period 2 (Weeks 7, 8, 9); Immediate crossover to opposite treatment than taken during Period 1:
Every 6H, supplied in 150 and 50mg capsules/Duration of Treatment: 3 weeks each period used; Period 1 (Weeks 4, 5, 6) or Period 2 (Weeks 7, 8, 9); Immediate crossover to opposite treatment than taken during Period 1:
Every 12H, supplied in 75 and 25mg capsules/Duration of Treatment: 3 weeks
Intervention MeSH terms: Cysteamine
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Enrollment: 43.0
Sex: All
Minimum age: 6 Years
Healthy volunteers: No
Keywords: cystinosis; cysteamine; inheritable disease; orphan disease; CTNS protein, human; metabolic disease; nephropathic cystinosis

Summary:

      Cystinosis is an inherited disease that if untreated, results in kidney failure as early as
      the first decade of life. The current marketed therapy is Cystagon® (cysteamine bitartrate)
      which must be taken every six hours for the rest of the patient's life to prevent
      complications of cystinosis. RP103 is a formulation of cysteamine bitartrate that is being
      studied to see if it may be able to be given less frequently, once every 12 hours, and have
      similar results to four times a day Cystagon®.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Male and female subjects must have nephropathic cystinosis.

          -  Subjects must be on a stable dose of Cystagon® sufficient to maintain their white
             blood cell (WBC) cystine level at ≤ 1.0 nmol/half-cystine/mg protein.

          -  Subjects must be able to swallow their typically administered Cystagon® capsule with
             the capsule intact.

          -  Within the last 6 months, no clinically significant change in liver function [i.e.,
             ALT, AST, total bilirubin] and renal function [i.e., estimated GFR] at Screening as
             determined by the Investigator.

          -  Subjects with an estimated GFR (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 or their parent or guardian must provide written informed consent
             and assent (where applicable) prior to participation in the study.

        Exclusion Criteria:

          -  Subject's age < 6 years old or subject's weight < 21 kg.

          -  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, 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 receiving any form of cysteamine medication through a gastric tube.

          -  Subjects who are receiving maintenance dialysis or who have had a kidney transplant.

          -  Subjects who are on an active kidney transplant list or who are planning to receive a
             kidney transplant within 3 months of Screening.

          -  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 have a made a blood donation within 30 days of Screening.

          -  Subjects who, in the opinion of the Investigator, are not able or willing to comply
             with the protocol.