FDA Approves Tolvaptan for Hyponatremia

May 27, 2009

May 27, 2009 (Silver Spring, Maryland) – The Food and Drug Administration has approved tolvaptan (Samsca, Otsuka America Pharmaceuticals), a selective vasopressin-receptor antagonist that can be taken orally, for the treatment of patients with clinically significant hypervolemic and euvolemic hyponatremia, including patients with heart failure, cirrhosis, and the syndrome of inappropriate antidiuretic hormone secretion.

The drug is approved with a warning that it should be started only in a hospital where serum sodium levels can be monitored closely. It is not approved for patients requiring urgent treatment to raise serum sodium to prevent or treat serious neurological deficits.

The approval follows last year's advisory panel recommendation for approval, a recommendation based largely on the Studies of Ascending Levels of Tolvaptan in Hyponatremia (SALT 1 and SALT 2). Those trials, previously reported by heartwire, suggested the drug could correct hyponatremia associated with heart failure, cirrhosis, and other disorders.

Hyponatremia is defined as a serum sodium concentration of <135 mmol/L and is associated with increased morbidity and mortality in patients with heart, liver, and neurologic disease.