(Adds details on the trial, shares)
Dec 18 (Reuters) - Allergan Plc and Hungary's Gedeon Richter Plc said on Monday their drug to treat severe bipolar depression in adults met the main goal of a late-stage study, bringing the them closer to getting another approval for the drug.
The drug, cariprazine, sold under the brand name Vraylar, is already approved to treat manic or mixed episodes of bipolar disorder and schizophrenia in adults.
The late-stage trial was testing two doses of cariprazine - 1.5 mg and 3 mg - in adults with major depressive episodes associated with bipolar disorder versus a placebo.
Bipolar disorder is characterized by dramatic shifts in mood, energy and activity levels that range from depressive lows to manic highs. It affects more than 5.7 million adults each year in the United States, according to the National Institute of Mental Health.
The companies said on Monday that both doses of the drug showed a statistically significant improvement in the severity of depressive episodes, as measured on the Montgomery-Asberg Depression Rating Scale (MADRS).
MADRS measures sadness, tension, suicidal thoughts and reduction of sleep and appetite in patients.
The companies said they would file an application to the U.S. Food and Drug Administration to get an additional approval for the drug in the second half of 2018.
Allergan's shares were marginally up in light premarket trading. (Reporting by Divya Grover in Bengaluru; Editing by Martina D'Couto)