A Fully Remote Randomized Trial of Transcranial Alternating Current Stimulation for the Acute Treatment of Major Depressive Disorder.

Objective: Major depressive disorder (MDD) is common, but current treatment options have significant limitations in terms of access and efficacy. This study examined the effectiveness of transcranial alternating current stimulation (tACS) for the acute treatment of MDD.Methods: We performed a triple-blind, fully remote, randomized controlled trial comparing tACS with sham treatment. Adults aged 21-65 years meeting DSM 5 criteria for MDD and having a score on the Beck Depression Inventory, Second Edition (BDI-II), between 20 and 63 were eligible to participate. Participants utilized tACS or sham treatment for two 20-minute treatment sessions daily for 4 weeks. The primary outcome was change in BDI-II score from baseline to the week 2 time point in an intent-to treat analysis, followed by analyses of treatment-adherent participants. Secondary analyses examined change at the week 1 and 4 time points, responder rates, subgroup analyses, other self-report mood measures, and safety. The study was conducted from April to October 2022.Results: A total of 255 participants were randomized to active or sham treatment. Improvement in intent-to-treat analysis was not statistically significant at week 2 (P= .056), but there were significant effects in participants with high adherence (P= .005). Significantly greater improvement at week 1 (P= .020) and greater response at week 4 (P= .028) occurred following tACS. Improvements were significantly larger for female participants. There were no significant effects on secondary mood measures. Side effects were minimal and mild.Conclusions: Rapid, clinically significant improvement in depression in adults with MDD was associated with tACS, particularly for women. Compared to other depression therapies, tACS has 3 key advantages: rapid, clinically significant treatment effect, the ability of patients to use the treatment on their own at home, and the rarity and low impact of adverse events.Trial Registration: ClinicalTrials.gov identifier: NCT05384041.

Efficacy and safety of a 4-week course of repeated subcutaneous ketamine injections for treatment-resistant depression (KADS study): randomised double-blind active-controlled trial.

BACKGROUND: Prior trials suggest that intravenous racemic ketamine is a highly effective for treatment-resistant depression (TRD), but phase 3 trials of racemic ketamine are needed. AIMS: To assess the acute efficacy and safety of a 4-week course of subcutaneous racemic ketamine in participants with TRD. Trial registration: ACTRN12616001096448 at www.anzctr.org.au. METHOD: This phase 3, double-blind, randomised, active-controlled multicentre trial was conducted at seven mood disorders centres in Australia and New Zealand. Participants received twice-weekly subcutaneous racemic ketamine or midazolam for 4 weeks. Initially, the trial tested fixed-dose ketamine 0.5 mg/kg versus midazolam 0.025 mg/kg (cohort 1). Dosing was revised, after a Data Safety Monitoring Board recommendation, to flexible-dose ketamine 0.5-0.9 mg/kg or midazolam 0.025-0.045 mg/kg, with response-guided dosing increments (cohort 2). The primary outcome was remission (Montgomery-Åsberg Rating Scale for Depression score ≤10) at the end of week 4. RESULTS: The final analysis (those who received at least one treatment) comprised 68 in cohort 1 (fixed-dose), 106 in cohort 2 (flexible-dose). Ketamine was more efficacious than midazolam in cohort 2 (remission rate 19.6% v. 2.0%; OR = 12.1, 95% CI 2.1-69.2, P = 0.005), but not different in cohort 1 (remission rate 6.3% v. 8.8%; OR = 1.3, 95% CI 0.2-8.2, P = 0.76). Ketamine was well tolerated. Acute adverse effects (psychotomimetic, blood pressure increases) resolved within 2 h. CONCLUSIONS: Adequately dosed subcutaneous racemic ketamine was efficacious and safe in treating TRD over a 4-week treatment period. The subcutaneous route is practical and feasible.