Treating bipolar depression with esketamine: Safety and effectiveness data from a naturalistic multicentric study on esketamine in bipolar versus unipolar treatment-resistant depression.

BACKGROUND: Bipolar depression accounts for most of the disease duration in type I and type II bipolar disorder (BD), with few treatment options, often poorly tolerated. Many individuals do not respond to first-line therapeutic options, resulting in treatment-resistant bipolar depression (B-TRD). Esketamine, the S-enantiomer of ketamine, has recently been approved for treatment-resistant depression (TRD), but no data are available on its use in B-TRD. OBJECTIVES: To compare the efficacy of esketamine in two samples of unipolar and bipolar TRD, providing preliminary indications of its effectiveness in B-TRD. Secondary outcomes included the evaluation of the safety and tolerability of esketamine in B-TRD, focusing on the average risk of an affective switch. METHODS: Thirty-five B-TRD subjects treated with esketamine nasal spray were enrolled and compared with 35 TRD patients. Anamnestic data and psychometric assessments (Montgomery-Asberg Depression Rating Scale/MADRS, Hamilton-depression scale/HAM-D, Hamilton-anxiety scale/HAM-A) were collected at baseline (T0), at one month (T1), and three months (T2) follow up. RESULTS: A significant reduction in depressive symptoms was found at T1 and T2 compared to T0, with no significant differences in response or remission rates between subjects with B-TRD and TRD. Esketamine showed a greater anxiolytic action in subjects with B-TRD than in those with TRD. Improvement in depressive symptoms was not associated with treatment-emergent affective switch. CONCLUSIONS: Our results supported the effectiveness and tolerability of esketamine in a real-world population of subjects with B-TRD. The low risk of manic switch in B-TRD patients confirmed the safety of this treatment.

Predicting outcome with Intranasal Esketamine treatment: A machine-learning, three-month study in Treatment-Resistant Depression (ESK-LEARNING).

Treatment-resistant depression (TRD) represents a severe clinical condition with high social and economic costs. Esketamine Nasal Spray (ESK-NS) has recently been approved for TRD by EMA and FDA, but data about predictors of response are still lacking. Thus, a tool that can predict the individual patients' probability of response to ESK-NS is needed. This study investigates sociodemographic and clinical features predicting responses to ESK-NS in TRD patients using machine learning techniques. In a retrospective, multicentric, real-world study involving 149 TRD subjects, psychometric data (Montgomery-Asberg-Depression-Rating-Scale/MADRS, Brief-Psychiatric-Rating-Scale/BPRS, Hamilton-Anxiety-Rating-Scale/HAM-A, Hamilton-Depression-Rating-Scale/HAMD-17) were collected at baseline and at one month/T1 and three months/T2 post-treatment initiation. We trained three different random forest classifiers, able to predict responses to ESK-NS with accuracies of 68.53% at T1 and 66.26% at T2 and remission at T2 with 68.60% of accuracy. Features like severe anhedonia, anxious distress, mixed symptoms as well as bipolarity were found to positively predict response and remission. At the same time, benzodiazepine usage and depression severity were linked to delayed responses. Despite some limitations (i.e., retrospective study, lack of biomarkers, lack of a correct interrater-reliability across the different centers), these findings suggest the potential of machine learning in personalized intervention for TRD.

Real-world experience of esketamine use to manage treatment-resistant depression: A multicentric study on safety and effectiveness (REAL-ESK study).

Background: Treatment-resistant Depression (TRD) represents a widespread disorder with significant direct and indirect healthcare costs. esketamine, the S-enantiomer of ketamine, has been recently approved for TRD, but real-world studies are needed to prove its efficacy in naturalistic settings. Objectives: Evaluate the effectiveness and safety of esketamine nasal spray in a clinical sample of patients with TRD from several Italian mental health services. Methods: REAL-ESK study is an observational, retrospective and multicentric study comprising a total of 116 TRD patients treated with esketamine nasal spray. Anamnestic data and psychometric assessment (MADRS, HAMD-21, HAM-A) were collected from medical records at baseline (T0), one month (T1) and three month (T2) follow-ups. Results: A significant reduction of depressive symptoms was found at T1 and T2 compared to T0. A dramatic increase in clinical response (64.2 %) and remission rates (40.6 %) was detected at T2 compared to T1. No unexpected safety concerns were observed, side effects rates were comparable to those reported in RCTs. No differences in efficacy have been found among patients with and without psychiatric comorbidities. Limitations: The open design of the study and the absence of a placebo or active comparator group are limitations. The study lacks an inter-rater reliability evaluation of the assessments among the different centres. Side effects evaluation did not involve any specific scale. Conclusions: Our findings support the safety and tolerability of esketamine in a real-world TRD sample. The later response and the non-inferiority in effectiveness in patients with comorbidities represent novel and interesting findings.