Merck says the FDA now has approved Saphris for ongoing treatment of schizophrenia and for treating acute mania or manic-depressive behavior in adult bipolar patients along with lithium, a mood-stabilizing drug often used to treat mania, or the antiseizure drug valproate.
Saphris carries the FDA's strongest caution, a black box warning, that it nearly doubles risk of death in elderly patients with dementia.
Like similar drugs, it has many other serious potential risks, including strokes, heart problems, high blood sugar and diabetes, suicide, seizures, fainting, a drop in infection-fighting white blood cells, sedation and impaired thinking, and neuroleptic malignant syndrome, a life-threatening neurological disorder.
Merck has not yet reported sales figures for Saphris, also known as asenapine.
Saphris, just launched in the fourth quarter, has lots of tough competition in the lucrative market for antipsychotic medicines, which are approved for treating schizophrenia and bipolar disorder. Rival drugs include Johnson & Johnson's Risperdal, Eli Lilly & Co.'s Zyprexa, AstraZeneca PLC's Seroquel, Pfizer Inc.'s Geodon and Bristol-Myers Squibb Co.'s Abilify.
The drugs are widely prescribed for unapproved uses, including other psychiatric conditions and insomnia, significantly boosting their sales.
Last year, antipsychotic drugs brought in $23.25 billion in worldwide sales, according to drug data firm IMS Health.
Saphris was developed by Schering-Plough Corp., which Merck bought last November.