No Heavy Drinking Days and Percentage of Days Abstinent in a Randomized Trial of Adjunctive Ketamine for Alcohol Use Disorder: Secondary Analysis of the KARE Trial

In the KARE trial, 96 adults with severe alcohol use disorder, abstinent following detoxification, were randomised in a 2×2 factorial design to 3 weekly infusions of ketamine (0.8 mg/kg) or saline, each combined with mindfulness-based psychological support (PS) or alcohol psychoeducation (PE). We re-expressed the trial data on endpoints acceptable to regulators and compared the most and least intensive arms. Across pooled weeks 17–24, ketamine plus PS gave 78.5% versus 57.8% days abstinent (difference, 20.7 percentage points; P = .032); adjusted for baseline, the difference at weeks 21–24 was 26.9 percentage points (P = .011). At weeks 21–24, 50.0% versus 26.1% had no heavy drinking days (P = .127). Relative reductions in heavy drinking days were 55% in KARE, against 25%, −17%, 46% and 35% reported for naltrexone, exenatide, semaglutide and pemvidutide. These post hoc differences, measured 4 to 6 months after a 4 week course ended, are of magnitude similar to agents requiring continuous administration.