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Open-Label Safety & Superior Effectiveness Study of Cysteamine Bitartrate Delayed-release Capsules (RP103) in Cystinosis

This study is ongoing, but not recruiting participants.
Information provided by (Responsible Party):
Raptor Pharmaceuticals Inc. Identifier:
First received: November 16, 2012
Last updated: October 3, 2016
Last verified: October 2016

The purpose of this study is to gather information about the effectiveness (how well it works to treat cystinosis) and safety of a new form of cysteamine bitartrate called RP103, compared to the already-approved drug cystinosis patients are taking called Cystagon®.

In cystinosis, the body builds up cystine. When taken regularly, the active ingredient of Cystagon® (cysteamine bitartrate) reduces cystine in the body. RP103 has the same active ingredient as Cystagon® and is designed to reduce cystine in a similar way that Cystagon® does. To decide if RP103 is better than Cystagon®, the study will look at two types of blood tests. One test is pharmacodynamics (PD), which measures the amount of white blood cell (WBC) cystine after taking study drug. WBC cystine is a laboratory test used to find out if cysteamine bitartrate is reducing cystine levels in the body. The second test is pharmacokinetics (PK), which measures the amount of cysteamine in the blood after taking the drug.

RP103 is different from Cystagon®: Instead of the cysteamine bitartrate being absorbed from the stomach, RP103 is designed to be absorbed from the small intestine. This may make the effects of the drug last longer, so that it can be taken twice a day instead of four times a day like Cystagon®.

Some cystinosis patients have bad breath (halitosis) when they take Cystagon®. Study participants who experience bad breath with Cystagon® will be asked if they would like to participate in an optional "halitosis substudy" to investigate this issue by collecting some extra PK blood samples.

Condition Intervention Phase
Drug: RP103 Q12H
Drug: Cystagon Q6H
Phase 3

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: A Long-Term, Open-Label, Safety and Superior Effectiveness Study of Cysteamine Bitartrate Delayed-release Capsules (RP103) in Patients With Cystinosis

Resource links provided by NLM:

Further study details as provided by Raptor Pharmaceuticals Inc.:

Primary Outcome Measures:
  • White Blood Cell (WBC) Cystine Levels [ Time Frame: 7 Months ]
    Superior effectiveness of RP103 vs. Cystagon® will be evaluated comparing WBC cystine levels during two 3-month treatment periods (Cystagon® and RP103). An interim analysis will be performed after 20 subjects complete the two treatment periods; A final analysis will be performed after all 60 subjects have completed.

  • Long-Term Safety and Tolerability [ Time Frame: 7 Months minimum; 24 months maximum ]
    The safety profile of RP103 will be investigated with the following assessments: physical examination, vital signs, ECG, clinical laboratory testing and adverse events.

Secondary Outcome Measures:
  • Quality of Life - General [ Time Frame: 7 months minimum; 24 months maximum ]
    Long-term general quality of life will be assessed using instruments appropriate to the subjects' age and region (US or Europe).

  • Quality of Life - Fatigue/Sleep [ Time Frame: 7 months; 24 months maximum ]
    Long-term quality of life, specifically fatigue/sleep, will be assessed using instruments appropriate to the subjects' age and region (US or Europe).

Estimated Enrollment: 60
Study Start Date: January 2013
Estimated Study Completion Date: June 2017
Primary Completion Date: February 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Cystagon Q6H
From Screening and during Months 1, 2, 3: all subjects will take Cystagon (cysteamine bitartrate) every 6 hours, supplied in 150 and 50mg capsules.
Drug: Cystagon Q6H
Other Name: Cystagon (cysteamine bitartrate)
Experimental: RP103 Q12H
From Months 3.5, 4, 5, 6, 7 and the remainder of participation: all subjects will take RP103 (cysteamine bitartrate delayed-release capsules) every 12 hours, supplied in 75 and 25mg capsules.
Drug: RP103 Q12H
Other Name: RP103 (cysteamine bitartrate delayed-release capsules)


Ages Eligible for Study:   12 Years and older   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No


  • Male or female with a documented diagnosis of cystinosis
  • On a stable dose of Cystagon at least 21 days prior to Screening
  • WBC cystine level > 1 nmol 1/2 cystine/mg of protein, on average over at least 2 measurements collected during the 2 years prior to Screening
  • No clinically significant change in liver function tests, i.e. 1.5 times ULN for ALT and 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 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 subjects 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.
  • Subject or their parent or guardian must provide written informed consent, assent (where applicable), prior to participation in the study


  • Younger than 12 years of age
  • Current history of the following conditions or any other health issues that make it, in the opinion of the investigator, unsafe for study participation:

    • Inflammatory bowel disease if currently active, or prior resection of the small intestine;
    • Heart disease (e.g., myocardial infarction, heart failure, unstable arrhythmias, or poorly controlled hypertension) within 90 days prior to Screening;
    • Active bleeding disorder within 90 days prior to Screening;
    • History of malignant disease within 2 years prior to Screening
  • Hemoglobin level of < 9 g/dL at Screening or, in the opinion of the investigator, a hemoglobin level that would make it unsafe for study participation
  • Known hypersensitivity to cysteamine and penicillamine
  • Female subjects who are nursing, planning a pregnancy, or are known or suspected to be pregnant
  • Subjects who, in the opinion of the investigator, are not able or willing to comply with study requirements
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01733316

United States, California
California Pacific Medical Center (CPMC) Research Institute
San Francisco, California, United States, 94115
Stanford University Medical School
Stanford, California, United States, 94305
United States, Georgia
Emory Children's Center
Atlanta, Georgia, United States, 30322
United States, Illinois
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, United States, 60614
United States, Texas
Baylor College of Medicine / Texas Childrens Hospital
Houston, Texas, United States, 77030
University Hospital of Leuven
Leuven, Belgium
Hospices Civils de Lyon
Lyon, France
Hôpital Robert Debré
Paris, France
Ospedale Pediatrico Bambino Gesù
Rome, Italy
Radboud University Nijmegen Medical Center
Nijmegen, Netherlands
United Kingdom
Queen Elizabeth Hospital Birmingham
Birmingham, United Kingdom
Great Ormond Street
London, United Kingdom
Guy's Hospital
London, United Kingdom
Sponsors and Collaborators
Raptor Pharmaceuticals Inc.
Principal Investigator: Laurence A Greenbaum, MD, PhD (US) Emory University
Principal Investigator: Georges Deschênes, MD, PhD (EU) Robert Debré Hospital
  More Information

Additional Information:
Responsible Party: Raptor Pharmaceuticals Inc. Identifier: NCT01733316     History of Changes
Other Study ID Numbers: RP103-07
2012-002773-64 ( EudraCT Number )
Study First Received: November 16, 2012
Last Updated: October 3, 2016

Keywords provided by Raptor Pharmaceuticals Inc.:
Nephropathic Cystinosis
Delayed-Release Cysteamine
Orphan Disease
CTNS Protein, Human

Additional relevant MeSH terms:
Lysosomal Storage Diseases
Metabolism, Inborn Errors
Genetic Diseases, Inborn
Metabolic Diseases
Cystine Depleting Agents
Molecular Mechanisms of Pharmacological Action processed this record on May 23, 2017