Background: Patients with major depressive disorder who do not respond to ≥2 different pharmacological treatments within the current depressive episode are considered to have treatment resistant depression (TRD). This analysis determined meaningful change thresholds (MCT) of the Patient Health Questionnaire (PHQ-9) and Montgomery-Åsberg Depression Rating Scale (MADRS) using anchor-based methods and compared proportions of meaningful changes in patients with TRD across treatment groups from two Phase 3 trials for esketamine nasal spray (SPRAVATOTM).
Methods: Data from two Phase 3 trials in patients with TRD, TRANSFORM-1 and -2, were used in this analysis. The MCTs for the PHQ-9 and MADRS were derived using a clinician global impression of severity anchor. Blinded probability density functions displayed score distributions between anchor categories. Proportions of meaningful response were compared between treatment groups using chi-square tests supported by unblinded cumulative distribution functions of change scores.
Results: Baseline scores were similar for the PHQ-9 and MADRS between the esketamine/antidepressant (AD) and AD/placebo groups. The most appropriate MCT on the PHQ-9 was -6 points. By Day 28, 86.5% of patients reached or exceeded the PHQ-9 MCT in the esketamine/AD group compared to 70% in the placebo/AD group. The most appropriate MCT for the MADRS was -10 points. By Day 28, 78.2% of patients reached or exceeded the MADRS MCT in the esketamine/AD group compared to 65.0% in the placebo/AD group.
Conclusions: Individual-level meaningful change for the PHQ-9 and MADRS was effectively quantified using a clinical anchor to interpret efficacy from patients with TRD and their treating clinicians.
Keywords: MADRS; Meaningful change threshold; PHQ-9; Quality of life; esketamine; treatment resistant depression.
Copyright © 2020. Published by Elsevier B.V.