Tolvaptan for In-hospital Hyponatremia

Summary

Hyponatremia is a common electrolyte disorder encountered in hospitalized patients. A preliminary, observational, feasibility analysis finalized to assess retrospectively the incidence of hyponatremia (Serum sodium \< 135 mEq/L) in a general medical-surgical hospital and the distribution of the cases of hyponatremia among different referral units showed that over one year observation there were more than 1500 cases of hyponatremia. Conventional therapy for hyponatremia depends on its causes, speed of onset, extracellular fluid volume status, and severity. Treatment consists in fluid restriction, normal or hypertonic saline, furosemide. Recent development of arginine vasopressin antagonists has provided a new therapeutic option for treatment of hyponatremia.Tolvaptan, an orally administered, nonpeptide, selective vasopressin V2 receptor antagonist reported to increase free water clearance and limit fluid retention in subjects with congestive heart failure or liver cirrhosis, has been also shown to be effective in the treatment of chronic hyponatremia in patients with SIADH, chronic heart failure, liver cirrhosis. Thus the investigators designed a clinical study to explore the incidence of severe hyponatremia in hospitalized patients in the setting of large general hospital and to evaluate whether tolvaptan is effective and safe in increasing serum sodium concentration in patients with normovolemic and hypervolemic hyponatremia in the setting of daily clinical practice. Moreover this study may help understand the cost-effectiveness of tolvaptan therapy compared to traditional treatments of hyponatremia.

Conditions

• Hyponatremia

Interventions

DRUG

Tolvaptan

Patients will receive full-dose oral tolvaptan therapy up to 1 month after randomization. During the initial 4 days of therapy, the dose of the study drug will be increased from 15 to 30 mg or from 30 to 60 mg according to a regimen designed for slow correction of serum sodium concentrations to 135 mEq/L or more Depending on the serum sodium concentration the dose will be increased or decreased. Patients will then be continued on their maintenance therapy with adjustments allowed to prevent hyponatremia and avoiding hypernatremia. As soon as normal serum sodium levels are achieved in at least two consecutive measurements the dose of the study drug will be progressively tapered according to an individually tailored weaning program

OTHER

Standard therapy

Fluid restriction, normal or hypertonic saline, furosemide.

Sponsors & Collaborators

• A.O. Ospedale Papa Giovanni XXIII

  collaborator OTHER

• Mario Negri Institute for Pharmacological Research

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2011-06-30

Primary Completion

2012-11-30

Completion

2012-11-30

Countries

• Italy

Study Locations