This double-blind, placebo-controlled therapeutic exploratory trial (n=60; PROUD) tests a two-week adjunctive subanaesthetic ketamine regimen (0.5 mg/kg IV) to improve retention in opioid-substitution treatment and prevent relapse in patients with opioid-use disorder.
PROUD is a Phase II, randomised, double-blind, placebo-controlled trial conducted at a single site in Cyprus evaluating whether a two-week regimen of subanaesthetic ketamine (0.5 mg/kg IV) adjunctive to opioid-substitution treatment improves retention and reduces relapse in people with opioid-use disorder.
Secondary objectives include assessment of ketamine’s effects on comorbid negative affect (depression, anhedonia, anxiety) and identification of biomarkers and EEG/neurophysiological predictors of vulnerability to relapse.
Outcomes include treatment retention, measures of affective symptoms, relapse rates up to nine months after last infusion, heart rate variability and stress biomarkers, and EEG spectral analyses.
Adjunctive subanaesthetic ketamine infusion regimen (0.5 mg/kg) versus placebo over a two-week treatment course.
Subanaesthetic antidepressant dosing as adjunct to opioid-substitution treatment.
Intravenous placebo solution matched to ketamine infusions.
Placebo intravenous solution; saline matched to active infusions.