NYMC Faculty Publications

Appraising Esketamine Nasal Spray for the Management of Treatment-Resistant Depression in Adults: Number Needed to Treat, Number Needed to Harm, and Likelihood to be Helped or Harmed

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Journal of Affective Disorders

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Psychiatry and Behavioral Sciences


INTRODUCTION: This post hoc study assessed the evidence-base for esketamine nasal spray for management of treatment-resistant depression (TRD) using number needed to treat (NNT), number needed to harm (NNH), and likelihood to be helped or harmed (LHH).

METHODS: Data sources were four phase III randomized, double-blind studies including two positive studies (acute flexible-dose; maintenance) in patients with TRD. Key efficacy study outcomes: acute response (≥50% decrease from baseline on Montgomery-Asberg Depression Rating Scale [MADRS] total score), acute remission (MADRS scores ≤12). NNT, NNH were calculated for esketamine nasal spray+newly initiated oral antidepressant (esketamine+AD) vs. placebo+AD.

RESULTS: In the pivotal acute flexible-dose study, MADRS response (63.4% vs. 49.5%) and remission (48.2% vs. 30.3%) at 4 weeks resulted in NNT of 8 and 6 for esketamine+AD vs. placebo+AD. NNH values(26.1% vs. 3.7%), vertigo (26.1% vs. 2.8%), nausea (26.1% vs. 6.4%), dizziness (20.9% vs. 4.6%), and dysgeusia (24.3% vs. 11.9%). Discontinuation rates due to adverse events (AE) (7.0% vs. 0.9%) yielded NNH=17. LHH comparing MADRS remission vs. discontinuation due to AE was 17 vs. 6. Maintenance use of esketamine+AD demonstrated NNT values/or maintenance of remission. In maintenance study, discontinuation due to AE (2.6% vs. 2.1%) yielded NNH=178 (non-significant).

LIMITATIONS: Only dichotomous outcomes were included.

CONCLUSION: NNTesketamine+AD for both acute and maintenance use. LHH was favorable: esketamine+AD was 3 times likely to result in acute remission vs. discontinuations due to AE.

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