NCT03572166: CARGOx

Use of Copeptin Measurement After Arginine Infusion for the Differential Diagnosis of Diabetes Insipidus - the CARGOx Study

Completed NA Last updated 27 July 2023

What this trial tests

NA trial testing Arginine infusion in Diabetes Insipidus in 177 participants. Completed in 31 December 2022.

Timeline

3 September 2018

Primary endpoint
30 September 2022

31 December 2022

Quick facts

Lead sponsor	University Hospital, Basel, Switzerland
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	crossover
Masking	single
Primary purpose	diagnostic
Enrollment	177
Start date	3 September 2018
Primary completion	30 September 2022
Estimated completion	31 December 2022
Sites	7 locations across Italy, Netherlands, United Kingdom, Germany, Switzerland, Brazil

Drugs / interventions tested

• Arginine infusion
• Hypertonic saline infusion — full drug profile →

Conditions studied

• Diabetes Insipidus — all drugs for Diabetes Insipidus →
• Polydipsia, Primary — all drugs for Polydipsia, Primary →

Sponsor

University Hospital, Basel, Switzerland

Who can join

Adults 18 to 95, any sex, with Diabetes Insipidus or Polydipsia, Primary. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

The differential diagnosis of central diabetes insipidus (cDI) is difficult and the current test with the highest diagnostic accuracy is copeptin measurement after hypertonic saline infusion (HIS). Although the HIS improved diagnostic accuracy compared to the standard water deprivation test used for decades before, it still comprises great discomfort for patients due to the rise in serum sodium levels above 149mmol/l and requires the presence of medical staff at all times to guarantee safety of the test.

The arginine stimulation test is routinely used to stimulate growth hormone. Own data in 52 patients with polyuria / polydipsia syndrome showed that arginine infusion is a potent stimulator of the neurohypophysis and provides a new diagnostic tool in the differential diagnosis of cDI. Copeptin measurements upon arginine stimulation (CAS) discriminated patients with diabetes insipidus vs. patients with primary polydipsia with a high diagnostic accuracy of 94%.

To validate these results and to compare them against the HIS a large multicenter trial is needed, where the diagnostic accuracy of the CAS is compared to the HIS.

Publications & conference data

6 peer-reviewed publications reference this trial (live from Europe PMC):

1. Arginine or Hypertonic Saline-Stimulated Copeptin to Diagnose AVP Deficiency.
   Refardt J, Atila C, Chifu I, Ferrante E, et al · · 2023 · cited 39× · PMID 37966286 · DOI 10.1056/nejmoa2306263
2. Approach to the Patient: "Utility of the Copeptin Assay".
   Christ-Crain M, Refardt J, Winzeler B. · · 2022 · cited 26× · PMID 35137148 · DOI 10.1210/clinem/dgac070
3. Diabetes insipidus: A rare endocrine complication of immune check point inhibitors: A case report and literature review.
   Angelousi A, Papalexis P, Karampela A, Marra M, et al · · 2023 · cited 7× · PMID 36561623 · DOI 10.3892/etm.2022.11709
4. A novel diagnostic score for diagnosing arginine vasopressin deficiency (central diabetes insipidus) or primary polydipsia with basal laboratory and clinical parameters: results from two international multicentre prospective diagnostic studies.
   Atila C, Chifu I, Drummond JB, Vogt DR, et al · · 2025 · cited 2× · PMID 40294614 · DOI 10.1016/s2213-8587(25)00053-1
5. Apelin levels in patients with polyuria-polydipsia syndrome upon copeptin stimulation tests.
   Bizzozero CA, Monnerat S, Chapman FA, Dhaun N, et al · · 2024 · PMID 39425917 · DOI 10.1093/ejendo/lvae138
6. Diagnosis and Treatment of Hereditary Central Diabetes Insipidus in a Swiss Family With a Mutation in the <i>AVP</i> Gene.
   Wyniger L, Beuret N, Rutishauser J, Seelig E. · · 2023 · PMID 37908243 · DOI 10.1210/jcemcr/luac023