Effect of Increasing Doses of Tiopronin on Cystine Capacity in Patients With Cystinuria (NCT03663855) | Clinical Trial Compass
CompletedPhase 2
Effect of Increasing Doses of Tiopronin on Cystine Capacity in Patients With Cystinuria
United States10 participantsStarted 2018-11-01
Plain-language summary
The purpose of this study is to determine the minimum effective dose of the cysteine binding thiol drug (CBTD) Tiopronin on urine cystine capacity, which is a measure of cystine solubility in the urine, in patients with cystinuria to evaluate the effect of escalating doses of cystine binding thiol drugs on the cystine capacity of the urine. The overall goal will be to help guide therapy and ultimately minimize unnecessary side effects caused by larger dosages.
Cystinuria is a rare genetic disease that can lead to significant morbidity in affected patients due to the recurrent nature of the disease. This study will follow the levels of urine cystine capacity in order to help guide treatment and to use lower than usually prescribed Tiopronin doses to decrease the potential side effects while maintaining therapeutic benefit. This will increase adherence with the medications by decreasing the burden of the large number of pills that need to be taken daily.
Who can participate
Age range
18 Years – 80 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Patients with a confirmed laboratory diagnosis of cystinuria who meet the following criteria: (1) stone analysis demonstrating cystine as a component, or (2) increased urinary cystine excretion (\>250mg/24hrs in adults).
* A medical regimen that includes Tiopronin.
* Willing to use a medically accepted form of birth control, if female and of child bearing- potential
* Ability to reliably urinate in a collection vessel and measure urine volume.
* Ability to give informed consent.
* Documentation of a stable complete blood count (CBC) and urinalysis (UA) in the six month period prior to the date of enrollment.
* Enrollment in Rare Kidney Stone Consortium (RKSC) Protocol 6401 (Cystinuria Registry)
Exclusion Criteria:
* Women who are pregnant, breastfeeding, or trying to become pregnant
* Patients with renal colic
* Patients who are scheduled to undergo a surgical procedure
* Inability to give informed consent
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.