Decision Resources, one of the world's leading research and advisory firms for pharmaceutical and healthcare issues, finds that surveyed psychiatrists say that the decrease in severity of manic symptoms is the attribute that most influences their prescribing decisions in bipolar mania. Clinical data and the opinions of interviewed thought leaders indicate that Eli Lilly's Zyprexa (olanzapine) has advantages in this attribute over AstraZeneca/Astellas's Seroquel (quetiapine), the sales-leading agent in the bipolar disorder drug market.
The new report entitled Bipolar Mania: Emerging Therapies That Offer a Reduced Risk of Weight Gain and Metabolic Side Effects Will Not Unseat Current Drugs Unless They Offer Efficacy Comparable to Olanzapine finds that a therapy that carries a risk of weight gain that is the same as, or better than, Bristol-Myers Squibb/Otsuka Pharmaceutical's Abilify (aripiprazole) would earn a higher patient share in Europe than in the United States, providing that it also offers dramatic improvements in efficacy relative to Abilify. According to the report, such a therapy would earn a 40 patient share in Europe and a 20 percent patient share in the United States, according to surveyed European and U.S. psychiatrists.
In 2009, Decision Resources' proprietary clinical gold standard for bipolar mania was Zyprexa. Based on available data and expert opinion, Zyprexa will retain clinical gold standard status for bipolar mania through 2018, owing primarily to its efficacy and delivery advantages relative to other current therapies for the indication. Although Abilify has gained an advantage on safety and tolerability attributes over all other assessed current therapies (including Zyprexa) -- an important driver of its sales -- Abilify is not perceived by interviewed psychiatrists as being as efficacious for bipolar mania as Zyprexa.
"Despite Zyprexa's propensity to cause weight gain and its metabolic side effects, it will remain the clinical gold standard through 2018," said Decision Resources Analyst Amy Jassen, Ph.D. "Thought leaders we interviewed do not expect any of the new antipsychotics entering this market by 2018 to provide better efficacy than Zyprexa for the treatment of bipolar mania."