A Phase 4 interventional study of Tiopronin 1g per day and Tiopronin 2g per day in Cystinuria, sponsored by NYU Langone Health. Completed at 1 site in United States. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2021-08-23.
Sponsored by NYU Langone Health · Phase 4, Interventional, and Treatment
The purpose of this study is to evaluate the effect of escalating doses of cystine biding thiol drugs, including tiopronin and d-penicillamine, on the urinary cystine capacity, which is a measure of the amount of cystine in the urine, in patients with cystinuria. The overall goal will be to help guide therapy and ultimately minimize unnecessary side effects caused by larger doses.
Cystinuria is a rare genetic cause of kidney stones that leads to significant morbidity due to the recurrent nature of the disease. As a result, a significant part of treatment is focused on prevention of stone formation. Current methods of prevention include increasing fluid intake, dietary modifications, alkali therapy, and cystine binding thiol drugs (CBTDs), which help increase the solubility of cystine in the urine. At present, the dosing of CBTDs is empiric, and not titrated to a specific measured effect. Our primary objective will be to measure the effect of increasing doses of CBTDs on cystine capacity. The investigators predict that higher dosages of these medications will lead to a more positive urinary cystine capacity, or the ability of urine to take up more cystine (and therefore decreased risk of stone formation). However, the dose at which increasing dosages of the medications cease to provide additional benefit is unknown. The investigators will directly measure the cystine capacity in the urine in response to increasing doses of medications to determine if there is a dose at which the maximum benefit of the drug exists.
This is a cross-over trial of escalating doses. There will be four parts to the study. In the first part, subjects will stop taking CBTDs for 7 days, and perform a 24-hour urine collection on day 7. In part 2, they will take their usual CBTD (either tiopronin or d-penicillamine) 1 gram per day for 7 days. They will perform another 24-hour urine collection on day 7 of this study period. In part 3, they will take their usual CBTD at 2 grams per day for 7 days and in part 4 they will take their CBTD at 3 grams per day for 7 days. Again, they will perform 24-hour urine collections on day 7 of each period. The order in which the parts of the study are performed will be randomized for each subject. The mean cystine capacities in each part of the study will be compared to determine the effect of drug dosage on urinary cystine capacity.
21 studies on the registry are indexed under Cystinuria; 5 are open to participants now.
Browse Cystinuria studies →NYU Langone Health is the lead sponsor of 1,430 studies on the registry; 258 are open to participants now.
Of its 235 completed or terminated interventional studies of FDA-regulated products, 197 (84%) have results posted.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Part 1: patients will stop taking CBTDs for seven days and perform a 24-hour urine collection on day 7 Part 2: patients will take their usual CBTD, either tiopronin or d-penicillamine, 1g per day for 7 days, taken as 500 mg twice a day Part 3: patients will take a total of 2g of tiopronin or D-penicillamine daily for 7 days Part 4: patients will take a total of 3g/d of tiopronin or D-penicillamine, also for a 7 day period
Drug: Tiopronin 1g per day · Drug: Tiopronin 2g per day · Drug: Tiopronin 3g per day
500mg PO BID x 7 days
Also known as: Thiola or tiopronin; d-penicillamine
1g PO BID x 7 days
Also known as: Thiola or tiopronin; d-penicillamine
1.5g PO BID x 7 days
Also known as: Thiola or tiopronin; d-penicillamine
Cystine Capacity
We will test for a negative correlation between progressive increases in doses of thiol drugs and cystine capacity
Time frame: 4 weeks on assigned therapy
| Milestone | CBTD Patients |
|---|---|
| Started | 10 |
| Completed | 10 |
| Not completed | 0 |
We will test for a negative correlation between progressive increases in doses of thiol drugs and cystine capacity
| mg/L | Increasing Doses of CBTD |
|---|---|
| Cystine Capacity | 43.1 ± 131.2 |
Collected over 10 Days. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| CBTD Patients | 0/10 (0%) | 0/10 (0%) | 0/10 (0%) |
| Age, Categorical(Participants) | CBTD Patients |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 10 |
| >=65 years | 0 |
| Sex: Female, Male(Participants) | CBTD Patients |
|---|---|
| Female | 7 |
| Male | 3 |
| Ethnicity (NIH/OMB)(Participants) | CBTD Patients |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 10 |
| Unknown or Not Reported | 0 |
| Region of Enrollment(participants) | CBTD Patients |
|---|---|
| United States | 7 |
PDFs hosted by the registry, ClinicalTrials.gov.
The record gives a start of Jun 2012, a primary completion of Dec 2017 and a completion of Dec 2017. It does not say whether these dates are actual or estimated.
Results were first posted in Aug 2021, 3 years 8 months after primary completion.
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This study is completed, as verified in Jul 2021. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Tiopronin