Safety and efficacy with esketamine in treatment-resistant depression: long-term extension study.
The international journal of neuropsychopharmacology – June 06, 2025
Source: PubMed
Summary
Breakthrough treatment offers hope for severe depression: Esketamine nasal spray shows remarkable long-term safety and efficacy in patients with treatment-resistant depression. Over 1,100 patients received treatment for up to 6.5 years, with nearly half achieving remission. The therapy maintained its effectiveness while showing manageable side effects, marking a significant advance for those who don't respond to traditional antidepressants.
Abstract
The rates of relapse and suicide risk are higher in treatment-resistant depression (TRD) vs non-treatment-resistant major depressive disorder. Even among patients with TRD who initially respond, the majority (70%) relapse within 6 months. To evaluate the long-term safety and efficacy of esketamine nasal spray, combined with an oral antidepressant, in patients with TRD. Phase 3, open-label, single-arm long-term extension study (SUSTAIN-3) conducted from June 2016 to December 2022. Outpatient. Adults with TRD who participated in ≥1 of 6 phase 3 "parent" studies continued esketamine by either entering a 4-week induction phase followed by an optimization/maintenance phase of variable duration (n = 458) or directly entering the optimization/maintenance phase of SUSTAIN-3 (n = 690), based on their individual response to study drug at the endpoint of the parent study. Intranasal esketamine dosing was flexible, twice-weekly during induction and individualized to depression severity during optimization/maintenance (weekly, every-other-week, or every-4-weeks), under direct supervision by site staff. To assess the long-term safety of esketamine. Efficacy endpoints included the change in depressive symptoms, assessed by the Montgomery-Åsberg Depression Rating Scale (MADRS). A total of 1148 patients were enrolled. Total exposure to esketamine was 3777 cumulative patient-years. Mean (median, range) exposure to esketamine in SUSTAIN-3 was 42.9 (45.8, range 0-79) months. The most common adverse events were headache (36.9%), dizziness (33.9%), nausea (33.6%), dissociation (25.5%), nasopharyngitis (23.8%), somnolence (23.1%), dysgeusia (20.2%), and back pain (20.0%). During the study, 5.3% and 6.4% of participants discontinued due to lack of efficacy or adverse event, respectively. Nine participants died: COVID-19-related (n = 3), pneumonia (n = 2), and completed suicide, myocardial infarction, multiple injuries, unknown cause (n = 1 each). The mean MADRS total score decreased during induction, and this reduction persisted during optimization/maintenance (mean [SD] change from baseline-to-phase endpoint of each phase: induction: -12.8 [9.73]; optimization/maintenance: + 0.2 [9.93]). A total of 35.6% of participants were in remission at the induction endpoint, and 48.5% and 49.6% at week 112 and optimization/maintenance endpoint, respectively. In the SUSTAIN-3 final dataset, no new safety signals were identified during long-term treatment with intermittently-dosed esketamine, combined with oral antidepressant, and improvement in depression generally persisted among participants who remained on maintenance treatment. These results add to the accumulated evidence on TRD treatment with esketamine. clinicaltrials.gov identifier: NCT02782104.