Aripiprazole Once-Monthly for Patients Diagnosed With Schizophrenia: Number Needed to Treat, Number Needed to Harm, and Likelihood to be Helped or Harmed.

Abstract

Objective: This post hoc analysis assessed the benefit-risk of aripiprazole once-monthly 400 mg (AOM 400) as acute and long-term maintenance treatment for patients diagnosed with schizophrenia, based on number needed to treat (NNT), number needed to harm (NNH), and likelihood to be helped or harmed (LHH).

Methods: Data were derived from 2 studies that evaluated efficacy and safety/tolerability of AOM 400 versus placebo in an acute or maintenance setting. Main efficacy outcomes were ≥30% reduction in Positive and Negative Syndrome Scale (PANSS) total score (acute treatment) and patients free from impending relapse (maintenance treatment); main safety/tolerability outcome was incidence of patient discontinuation due to treatment-emergent adverse events (TEAEs). NNT, NNH, and LHH were calculated using standard methods.

Results: In the acute study, 60/167 AOM 400 recipients (37.0%) versus 24/168 placebo recipients (14.4%) had a ≥30% reduction in PANSS total score at week 10 (NNT=5 [95% confidence interval (CI), 4-8]). Corresponding values for avoidance of impending relapse in the maintenance study (median observation time: 113 days) were 242/269 (90.0%) versus 81/134 (60.4%) (NNT=4 [95% CI, 3-5]). Discontinuations due to TEAEs were lower with AOM 400 versus placebo in both studies, resulting in negative NNH values. Calculated LHH values were 200 (acute treatment) and 250 (maintenance treatment), indicating a higher likelihood to be helped than harmed with AOM 400.

Conclusion: Data demonstrate a favorable benefit-risk profile for AOM 400 versus placebo in the acute and maintenance treatment of schizophrenia.

Trial Registration: ClinicalTrials.gov identifiers: NCT01663532 and NCT00705783.