TCUPS- Tolvaptan Use in Cystinuria and Urolithiasis: A Pilot Study (TCUPS)
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ClinicalTrials.gov Identifier: NCT02538016 |
Recruitment Status :
Completed
First Posted : September 2, 2015
Results First Posted : June 4, 2020
Last Update Posted : July 10, 2020
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Cystinuria | Drug: Tolvaptan | Not Applicable |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 4 participants |
Allocation: | N/A |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Use of Tolvaptan, a Vasopressin Antagonist, to Increase Urine Dilution and Reduce Cystine Urolithiasis Among Patients With Homozygous Cystinuria: a Pilot Investigation |
Study Start Date : | October 2016 |
Actual Primary Completion Date : | December 2018 |
Actual Study Completion Date : | December 2018 |

Arm | Intervention/treatment |
---|---|
Tolvaptan |
Drug: Tolvaptan |
- Urinary Cystine Supersaturation (mg/L) at High Dose (Day7-8) [ Time Frame: 23 days ]The primary outcome was urinary cystine supersaturation as measured by "cystine capacity". This proprietary test (Litholink Corp., Chicago IL) is reported as a value in mg/L above or below zero, with positive values indicating urine undersaturated with cystine, while negative values indicate that the urine is supersaturated with cystine. Four 24-hour urine samples were obtained during the study: one at baseline 3-6 days prior to the measurement, one on day 3-4 of the dosing period, one on day 7-8 of the dosing period, and one 3-6 days after the washout period. Each 24 hour urine sample was sent individually for analysis by Litholink Corp, which performs the cystine assays.
- Urine Osmolality at High Dose (Day 8) [ Time Frame: 11 days ]Secondary outcomes included serum sodium and other electrolyte levels. Serum electrolytes for each subject before, during, and after tolvaptan treatment (Sodium/Potassium/Chloride in mmol/L).

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Ages Eligible for Study: | 12 Years to 29 Years (Child, Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Males and females age 12 - 29 years
- Weight ≥ 25kg (55 lbs)
- Confirmed cystinuria diagnosis
- Specific blood test levels (done within the past 6 months)
Exclusion Criteria:
- Concurrent non-renal disease that might increase risk of complications due to aquaresis
- Liver or biliary disease (chronic or acute)
- Malabsorption syndrome or other gastrointestinal condition that may interfere with response to therapy
- Non-cutaneous malignancy within last 5 years
- History of adverse reaction or allergy to Tolvaptan or other arginine vasopressin V2-receptor antagonists

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02538016
United States, Massachusetts | |
Boston Children's Hospital | |
Boston, Massachusetts, United States, 02115 |
Principal Investigator: | Caleb Nelson, MD, MPH | Boston Children's Hospital |
Documents provided by Caleb Nelson, Boston Children's Hospital:
Responsible Party: | Caleb Nelson, MD, MPH, Boston Children's Hospital |
ClinicalTrials.gov Identifier: | NCT02538016 |
Other Study ID Numbers: |
16726 |
First Posted: | September 2, 2015 Key Record Dates |
Results First Posted: | June 4, 2020 |
Last Update Posted: | July 10, 2020 |
Last Verified: | May 2020 |
Cystinuria Kidney Stones |
Urolithiasis Urinary Calculi Cystinuria Urologic Diseases Calculi Pathological Conditions, Anatomical Renal Aminoacidurias Renal Tubular Transport, Inborn Errors |
Kidney Diseases Genetic Diseases, Inborn Tolvaptan Antidiuretic Hormone Receptor Antagonists Molecular Mechanisms of Pharmacological Action Natriuretic Agents Physiological Effects of Drugs |