Cannabidiol effects on cognition in individuals with cocaine use disorder: Exploratory results from a randomized controlled trial

Background: Cocaine use disorder (CUD) is associated with various cognitive deficits that impede patients' functionality, prognosis and therapeutic outcomes. New pharmacological treatments for CUD that could improve cognition are needed. Objective: To explore whether cannabidiol (CBD) is superior to placebo to improve cognitive functioning in individuals with CUD. Methods: We conducted an exploratory analysis of a single site, randomized, double-blind, placebo-controlled trial evaluating CBD's efficacy in reducing craving, cocaine use and relapse in individuals with CUD. Seventy-eight individuals diagnosed with CUD were randomized to receive either CBD (800 mg) or placebo for 92 days. We used the Cambridge Neuropsychological Test Automated Battery (CANTAB) to assess inhibition (Stop Signal Task; SST), risky decision making (Cambridge Gambling Task; CGT) and visual memory (Pattern Recognition Memory; PRM). This assessment was made on day 1, day 7 and at week 6. We controlled for sex, severity of dependence and baseline cognitive scores in our generalized estimating equation models. Results: Both groups performed similarly on the PRM (correct answers: p = 0.080), SST (stop signal reaction time: p = 0.644) and CGT (quality of decision making: p = 0.994; deliberation time: p = 0.507; delay aversion: p = 0.968; risk taking: p = 0.914) tests. Conclusions: We found no evidence for 800 mg of CBD to be more efficacious than placebo for improving cognitive outcomes. Clinical trials evaluating pharmacological treatments for CUD should continue to be a research priority.