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.
Phase:
Phase 2
Details
Lead Sponsor:
Mario Negri Institute for Pharmacological Research