Pilot Study of Safety, Tolerability, Pharmacokinetics/Pharmacodynamics of RP103 Compared to Cystagon® in Patients With Cystinosis
Cystinosis is an inheritable 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.
|Study Design:||Allocation: Non-Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||A Pilot Study to Assess the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of Cysteamine Bitartrate Delayed-release Capsules (RP103), Compared to Cysteamine Bitartrate (Cystagon®) in Patients With Nephropathic Cystinosis|
- Plasma Pharmacokinetic Parameter: Cmax of Cysteamine [ Time Frame: 12 hours post RP103 dosing and 7 hours post 1st Cystagon® dosing ] [ Designated as safety issue: No ]
- Plasma Pharmacokinetic Parameter: Tmax of Cysteamine [ Time Frame: 12 hours post RP103 dosing and 7 hours post 1st Cystagon® dosing ] [ Designated as safety issue: No ]
- Plasma Pharmacokinetic Parameter: AUC(0-t) of Cysteamine [ Time Frame: 12 hours post RP103 dosing and 6 hours post 1st Cystagon® dosing ] [ Designated as safety issue: No ]t = 6 for Cystagon and t = 12 for RP103. Cystagon is dosed every 6 hours and there is no measurement after 6 hours and up to 12 hours.
- Pharmacodynamic Parameter: Changes of White Blood Cell (WBC) Cystine Level From Baseline [ Time Frame: up to 12 hours post Cystagon® dosing and RP103 dosing ] [ Designated as safety issue: No ]
The pharmacodynamic (PD) parameter measures the changes of WBC cystine level from the baseline.
Cystine is a disulfide amino acid formed through oxidation of two molecules of cysteine; hence, cystine's concentration is commonly given in half-cystine equivalents to avoid confusion.
The level of cystine in WBC/leukocytes is expressed in units of nmol half-cystine/mg protein (nmol ½ cystine/mg protein). Half-cystine is quantified by a reduction of cystine followed by an assay for cysteine, which is then normalized by the total cellular protein content within the sample using methods of such as Lowry assay, bicinchoninic acid assay, or Bradford.
|Study Start Date:||May 2009|
|Study Completion Date:||October 2009|
|Primary Completion Date:||October 2009 (Final data collection date for primary outcome measure)|
Active Comparator: Cystagon®
Reference Product: Cystagon® (Cysteamine Bitartrate) Capsules, 150 mg/50 mg
Reference Product: Cystagon® (Cysteamine Bitartrate) Capsules, 150 mg/50 mg.
Duration of Treatment and Dose: Reference Period up to four doses Q6H.
Test Product: RP103 (Cysteamine Bitartrate) Delayed-release Capsules, 75 mg
Test Product: RP103 (Cysteamine Bitartrate) Delayed-release Capsules, 75 mg.
Duration of treatment and Dose: Single dose of Test Product at dose equivalent to Reference Product.
This is a single-dose, open-labeled, non-randomized, two-period study of Cysteamine Bitartrate Delayed-release Capsules (RP103) and Cystagon® in up to 10 patients (male or female) with nephropathic cystinosis under fasting conditions. It will involve a 4 night check-in to a clinical research center.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00872729
|United States, California|
|University of California San Diego Medical Center|
|San Diego, California, United States, 92103|
|Principal Investigator:||Bruce Barshop, MD, PhD||UCSD|