Most adverse events were mild to moderate, but six patients experienced serious adverse events that were possibly related to the study drug, including disorientation, hypothermia, lacunar stroke, sedation, and suicidal ideation, during the induction phase of the study. However on review, the study sponsor argued that the lacunar stroke and hypothermia were unlikely to be linked to the study medication.
Four patients in the esketamine group and three patients in the placebo group discontinued the nasal spray during the maintenance phase.
“The study provides support for a positive benefit-risk evaluation for treatment with esketamine plus an oral antidepressant and provides further safety data regarding longer-term, intermittent dosing frequency treatment,” wrote Ella J. Daly, MD, from Janssen Research & Development – which also funded the study – and coauthors.
The researchers also noted that, overall, cognitive performance remained stable or improved after long-term, intermittent treatment with the esketamine nasal spray plus antidepressant.