SAN ANTONIO, TX—The atypical antipsychotic asenapine improves pediatric bipolar symptoms among children with different stages of disease progression, according to a post-hoc analysis of children with bipolar mania, presented at the U.S. Psychiatric & Mental Health Congress.

“Overall, asenapine is generally efficacious in pediatric patients with bipolar disorder experiencing a manic or mixed episode regardless of the stage of disease progression,” reported lead study author Roger S. McIntyre, MD, of the Toronto Western Research Institute in Ontario, Canada, and coauthors.

“Analysis by dose showed no apparent dose-related differences in asenapine efficacy in patients at different stages of illness, although small sample sizes precluded definitive conclusions about differences by dose,” they cautioned.

Asenapine monotherapy is approved for treatment of manic or mixed bipolar I disorder episodes in children aged 10 to 17 years. Because bipolar disorder is progressive and episodic, and because recurrence risk and symptom severity climb with increasing numbers of acute episodes, optimal treatment requires a better understanding of pharmacotherapeutic efficacy profiles among patients at different stages of disease, the authors argued.

They therefore conducted a post-hoc analysis of a study of 403 children, to examine the associations between asenapine efficacy and stage of disease among patients with pediatric bipolar mania. Disease stage was quantified as the number of previous manic or mixed bipolar episodes and efficacy outcomes were assessed as change at Day 21 from baseline for Young Mania Rating Scale (YMRS) total score (the primary outcome) and change from baseline in Clinical Global Impression-Bipolar Illness-Severity (CGI-BP-S) overall score.

Study participants were randomly assigned to a placebo group (n=101) or one of three asenapine twice-daily treatment dose groups: 2.5mg (n=104), 5mg (n=99), or 10mg (n=99).

“When evaluated by the number of previous manic or mixed episodes experienced, asenapine had generally similar effects across subgroups on both the YMRS and CGI-BP-S, there was no apparent pattern of meaningful dose-related differences in any subgroup,” the authors reported.

However, in patients who had previously experienced more than 5 episodes, the 2.5mg and 10mg doses were both significantly more effective than placebo, when either YMRS or CGI-BP-S criteria were used (for both criteria: 2.5mg, P<0.05 vs. placebo; for 10mg, P<0.001).

When treatment-dose groups were pooled for analysis, asenapine treatment was associated with significantly better CGI-BP-S efficacy than placebo across disease progression stages (P<0.001 for patients with fewer than 3 episodes and P<0.01 for 3 or more episodes).

The study was funded by Merck and Co., Inc. Dr. McIntyre disclosed advisory board membership and speaker’s fees involving Bristol-Myers Squibb, Eli Lilly, Pfizer, Lundbeck, Takeda, and other companies.