DOW JONES NEWSWIRES 
 

The Food and Drug Administration gave final approval to Schering-Plough Corp.'s (SGP) asenapine, a treatment for both schizophrenia and bipolar disorder in adults.

The drug, which will be sold under the brand name Saphris, is expected to be available in the U.S. in the fourth quarter.

The company said it is the first psychotropic drug to receive initial approval to treat both mental disorders and is the first product from its 2007 acquisition of Organon Biosciences.

The approval comes as Schering-Plough is poised to merge with Merck & Co. (MRK), after shareholders at both companies approved the deal last week.

The FDA decision was based on a clinical study involving more than 3,000 patients with acute schizophrenia or bipolar mania, with patients followed for as long as two years.

Saphris and other so-called atypical antipsychotic drugs all have "significant risks" including sedation, weight gain, and, over time, concerns about diabetes and other conditions linked to weight gain. The drugs can also cause a serious movement disorder called tardive dyskinesia.

Schizophrenia afflicts about 1% of Americans and is a major contributor to suicide. According to the National Institute of Mental Health, people with schizophrenia may hear voices other people don't hear or they may believe that others are reading their minds, controlling their thoughts or plotting to harm them.

Bipolar disorder, also known as manic-depressive illness, is believed to affect about 1% to 3% of the U.S. population.

Schering-Plough shares are up 0.7% premarket at $27.29. The shares are up by a third in the past year.

-By Tess Stynes, Dow Jones Newswires; 212-416-2481; tess.stynes@dowjones.com