KET01 Oral Prolonged-Release Ketamine for TRD: 3-Arm RCT (Colla 2024, 3 Swiss Hospitals)

Three-arm double-blind RCT at three Swiss psychiatric hospitals (J Psychiatr Res 2024; Colla M, Offenhammer B, Scheerer H, Kronenberg G; PMID 38522166; April 2019 – December 2021, with COVID-19 recruitment hiatus). Study code: KET01. Registered on Swiss National Clinical Trials Portal (SNCTP); registration number not recoverable from methods. Participants: adults 18–70, ICD-10 major depressive episode, MADRS ≥19, failed ≥2 adequate antidepressant trials, BMI 18–30; exclusions: psychosis/dementia, active suicidality, substance dependence, serious medical comorbidity. 1:1:1 block randomisation (block size 6, stratified by age/sex/weight) to: placebo vs KET01 160 mg/day (80 mg BID) vs KET01 240 mg/day (120 mg BID) for 14 days. Ongoing antidepressants maintained without washout. Target: n=33/arm (n=99 total); recruitment curtailed before target. Primary outcome: MADRS change baseline to day 15; MADRS also assessed days 1, 2, 4, 7, 11. CT.gov: 0 hits.