Olanzapine More Effective against Manic Relapse: Bipolar I Disorder Study
McNamara, Damian, Clinical Psychiatry News
BOCA RATON, FLA. -- Olanzapine and lithium both effectively prolonged remission in people with bipolar disorder, but olanzapine was superior at preventing relapse into mania for up to 1 year, according to a randomized, double-blind study.
"We wanted [olanzapine] to be equal to lithium in efficacy, or at least we wanted to show that it wasn't inferior. We didn't expect it to be superior," Dr. Daniel P. McDonnell said. "It was a pretty high target. This is the first time any treatment has beaten lithium in any study of bipolar disorder," added Dr. McDonnell, a clinical research physician at Eli Lilly & Co. in Indianapolis, the manufacturer of Zyprexa (olanzapine). He reported the results at a meeting of the New Clinical Drug Evaluation Unit, sponsored by the National Institute of Mental Health.
The researchers selected 543 people with a diagnosis of bipolar I disorder, manic or mixed type, who reported at least two manic or mixed episodes in the previous 6 years. All had a score of at least 20 on the Young Mania Rating Scale (YMRS). The patients received combination therapy with lithium and olanzapine for 6-12 weeks until they were in remission. A total of 431 met the remission criteria: a YMRS score of 12 or less and a score on the 21-item Hamilton Depression Rating Scale of 8 or less.
These 431 participants were randomized to lithium or olanzapine monotherapy for 52 weeks. The mean YMRS score at randomization was 3.9 in the lithium group and 3.6 in the olanzapine group. Patient demographics were similar in the different groups. The mean age was 42, and 53% of the participants were female.
The primary aim was to compare the two agents in terms of symptomatic relapse of bipolar disorder, defined as either mania or depression.
Of the 431 patients, 46 discontinued treatment during the 4-week period when they were tapering off combination therapy, and another 214 dropped out during the remaining 48 weeks. …