To report functional recovery, symptomatic remission, and sustained symptomatic remission rates after treatment with aripiprazole once-monthly 400mg (AOM 400) administered every 4weeks for up to 52weeks as maintenance treatment in a mixed cohort of AOM 400 naïve (de novo) and experienced adults (rollover) with bipolar I disorder (BP-I).

This open-label study (NCT01710709) enrolled de novo patients with a diagnosis of BP-I and ≥1 previous manic or mixed episode and rollover patients who completed a randomized, double-blind, placebo-controlled study assessing the efficacy and safety of AOM 400 (NCT01567527). Efficacy was assessed by mean changes from baseline in Young-Mania Rating Scale (YMRS), Montgomery-Asberg Depressive Rating Scale (MADRS), and Clinical Global Impression- Bipolar Version-Severity of Illness (CGI-BP-S) scores. Sustained functional recovery was defined as a total score of ≤11 on the Functioning Assessment Short Test (FAST) for ≥8 consecutive weeks. Remission was defined as YMRS and MADRS total scores ≤12, and sustained remission was defined as meeting criteria for remission for 8 consecutive weeks. The study included a screening phase (6weeks) for de novo patients, an oral aripiprazole conversion phase (4–6weeks), an oral stabilization phase (4–12weeks), and an AOM 400 maintenance phase (up to 52weeks). Rollover patients entered directly into the AOM 400 maintenance phase.

A total of 464 subjects entered the maintenance phase and 63% (291/464) completed the trial. Of patients entering the maintenance phase, 379 (82%) were de novo and 85 (18%) were rollover. The most frequent reasons for discontinuation were withdrawal of consent (11%) and adverse events (AEs) (10%). Weight increase (1.5%, 7/464) and BP-I (0.9%, 4/464) were the most common reasons for discontinuation due to AEs. Improvements in mean YMRS, MADRS, CGI-BP-S, and FAST scores achieved in previous phases were maintained over 52weeks. Treatment-emergent AEs experienced by >10% of the patients were akathisia (14.7%), weight increased (13.4%), nasopharyngitis (12.1%), and insomnia (11.0%). A high proportion of de novo patients met the criteria for symptomatic remission (87.2%, 328/376) and sustained remission (77%, 292/379) by last visit. Rollover patients’ remission rate remained stable (98.8%, 84/85) by last visit. Of the rollover patients, 35/85 (43%) and 35/116 (36%) of de novo subjects met the criteria for sustained functional recovery after study completion.

Patients treated with AOM 400 maintained symptomatic and functional stability for up to 52weeks. Importantly, more than one-third of patients achieved sustained functional recovery using a strict criterion. Overall, AOM 400 was safe and well tolerated in patients with BP-I. Results support AOM 400 as a viable once-monthlyoption for maintenance treatment of BP-I.

These data were previously presented at the 31st ECNP Congress, 2018, Barcelona,Spain.

Funding Acknowledgements: The study was supported by Otsuka Pharmaceutical Development & Commercialization, Inc.