For patients with treatment-resistant depression, adjusting how often they use esketamine nasal spray based on their symptoms can help maintain or improve treatment response. In an open-label study of 778 patients, those who responded to twice-weekly esketamine during a 4-week induction phase then had their treatment frequency reduced to weekly. After four weeks of weekly treatment, 26% of 580 responders continued to improve, 50% maintained benefit, and 24% worsened. When frequency was further reduced to every other week, 19% improved, 49% maintained benefit, and 32% worsened. For patients who lost remission after reducing frequency, increasing back to weekly led to 47% improving, 43% staying the same, and 10% worsening. These results suggest that personalizing esketamine treatment frequency can optimize outcomes.
A post hoc analysis of two pooled 4-week phase 3 trials examined predictors of response and remission in patients with treatment-resistant depression receiving esketamine nasal spray plus a new oral antidepressant compared to a new oral antidepressant plus placebo nasal spray. Younger age, being employed, having fewer failed antidepressants in the current episode, and early reduction in Clinical Global Impression-Severity score at day 8 predicted better outcomes. Those on esketamine had 68% higher odds of response and 55% higher odds of remission. In the esketamine group, response was more likely in employed patients, those without baseline anxiety, and those with early symptom improvement.
Dissociation encompasses distinct phenomena, some linked to esketamine treatment and potentially overlapping with psychosis symptoms. In a post hoc analysis of data from an open-label, phase 3 study of esketamine plus a newly initiated oral antidepressant in patients with treatment-resistant depression, dissociation was reported as an adverse event in 14.3% (109/764) of patients. CADSS scores generally aligned with investigator-reported dissociation severity, but no cutoff point reliably distinguished presence from absence of dissociation events. Hallucinations occurred in 5 patients, and no delusions were reported, indicating psychotic symptoms were uncommon.