Status
Completed
Phase
Not applicable
Enrollment
42
Locations
1
Results
Not posted
Publications
0
Study summary
The aims of this study are to investigate whether mannitol stimulates copeptin (part 1: proof-of-concept) and whether the copeptin levels upon mannitol infusion differ in primary polydipsia and arginine vasopressin deficiency (part 2: pilot study).
Diagnosing polyuria-polydipsia syndrome, which includes arginine vasopressin (AVP) deficiency (AVP-D, formerly central diabetes insipidus) and primary polydipsia (PP), is challenging but essential. Currently, the most accurate test currently involves measuring copeptin after osmotic stimulation with hypertonic saline, but this test is rarely used due to the need for close sodium monitoring and the discomfort it can cause. Mannitol has been shown to stimulate AVP release, but no study has tested copeptin levels after mannitol stimulation in healthy adults or patients with AVP-D or PP. This single-center study is conducted in two consecutive parts. Part 1 is a double-blind, randomized cross-over proof-of-concept study in healthy adults to investigate if mannitol infusion stimulates copeptin release. Part 2 is an open-label, single arm case-control pilot study in adults with diagnosed PP or AVP-D to see if copeptin levels after mannitol stimulation differ in PP and AVP-D. The results of this study aim to demonstrate if mannitol infusion has the potential to be used as an alternative to hypertonic saline infusion.
Interventions
DIAGNOSTIC_TEST
1 g of mannitol per kg body weight is infused in 30 minutes (≙ 5 ml/kg body weight), with an upper limit of 80 g, equivalent to a body weight of 80 kg or a volume of 400 ml. The solution used for infusion is 20% mannitol in water for injection and is administered at a rate of 0.17 ml/kg/min.
DIAGNOSTIC_TEST
0.9% saline will be administered in the same amount as the mannitol dose infusion (= 5 ml/kg body weight), with a rate of 0.17 ml/kg/min in 30 minutes, with an upper limit of 400 ml (equivalent to a body weight of 80 kg).
DIAGNOSTIC_TEST
1.5 g of mannitol per kg body weight is infused in 30 minutes (≙ 7.5 ml/kg body weight), with an upper limit of 120 g, equivalent to a body weight of 80 kg or a volume of 600 ml. The solution used for infusion is 20% mannitol in water for injection.
Timeline
First posted
Aug 7, 2024
Study start
Sep 10, 2024
Primary completion
Jul 22, 2025
Study completion
Jul 22, 2025
Results posted
Not reported
Registry updated
Dec 15, 2025
Outcomes
Difference in copeptin levels
Time frame · Part 1: At 90 min post infusion, Part 2: at 30 min post infusion
The difference in copeptin levels at 90 minutes following a 30-minute infusion of mannitol, part 1: compared to placebo in healthy adults and part 2: between patients with (primary polydipsia) PP and arginine vasopressin deficiency (AVP-D)
Change of copeptin levels
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
Changes in copeptin levels compared to baseline.
Maximum copeptin levels
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
The maximum copeptin level after infusion is determined.
Assessment of hormone level
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in hormone levels, an assessment of hormones (e.g. Adrenocorticotropic hormone, Growth hormone, Insulin-like growth factor 1) is performed.
Assessment of serum electrolytes
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in electrolytes, an assessment of electrolytes (e.g. sodium potassium, chloride) in the serum is performed.
Assessment of plasma osmolality
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in parameters associated with fluid balance/ kidney function, an assessment of plasma osmolality (mOsm/kg) is performed.
Assessment of urea
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in parameters associated with fluid balance/ kidney function, an assessment of ureal levels (mmol/L) is performed.
Assessment of uric acid
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in parameters associated with fluid balance/ kidney function, an assessment of uric acid levels (umol/L) is performed.
Assessment of creatinine
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in parameters associated with fluid balance/ kidney function, an assessment of creatinine levels (umol/L) is performed.
Assessment of glucose
Time frame · Part 1: At baseline, 30, 45, 60, 90, and 150 min after infusion, Part 2: At baseline, 30 and 90 minutes
To determine the change in parameters associated with fluid balance/ kidney function, an assessment of glucose levels (mmol/L) is performed.
Assessment of urine parameters
Time frame · Part 1: At baseline, 90 and 150 min after infusion, Part 2: At baseline, 30 and 90 min after infusion
To determine the change in urine parameters, an assessment of parameters (e.g. sodium, osmolality, creatinine) in the urine is performed.
Eligibility
Inclusion Criteria: Part 1: Proof of Concept in Healthy adults * Age ≥ 18 years * Healthy with no medication except hormonal contraception Part 2: Pilot Study in Patients with primary polydipsia (PP) or arginine vasopressin deficiency (AVP-D) * Age ≥ 18 years * Evidence of polyuria \> 40-50 ml/kg body weight per 24 hours and polydipsia \> 3 Liter per 24 hours or regular desmopressin medication corresponding to a diagnosis of PP or AVP-D Exclusion Criteria: Part 1: Proof of Concept in Healthy adults * Participation in a trial with investigational drugs within 30 days * Evidence of disordered drinking habits and diuresis defined as polyuria \> 40-50 ml/kg body weight per 24 hours and polydipsia \> 3 Liter per 24 hours. * Estimated Glomerular Filtration Rate (eGFR) \< 60 ml/min/1,73 m2 * Glucose \> 11.1 mmol/L corresponding to the diagnosis of an uncontrolled diabetes mellitus * History of urinary tract obstruction * Problems with urination * Pregnancy or breastfeeding * Multiple allergies (≥ 3) * Evidence of acute illness Part 2: Pilot Study in Patients with PP or AVP-D * Participation in a trial with investigational drugs within 30 days * Pregnancy or breastfeeding * Evidence of acute illness * eGFR \< 60 ml/min/1,73 m2 * Glucose \> 11.1 mmol/L corresponding to the diagnosis of uncontrolled diabetes mellitus * History of urinary tract obstruction * Problems with urination * Therapy with diuretics * Multiple allergies (≥ 3)
Study locations
Switzerland. Showing up to 24 locations stored in the fast local snapshot.
University Hospital Basel
Basel, Switzerland
Publications
No PMID-linked publications were present in this registry snapshot.
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