A recent study published in the American Journal of Psychiatry provides compelling evidence that reducing cannabis use, even without achieving complete abstinence, can lead to significant improvements in cannabis-related problems and functional outcomes for individuals with cannabis use disorder. This finding has important implications for the development of new treatments and the establishment of clinically meaningful endpoints in substance use disorder research.
The study, led by McClure and colleagues, conducted a secondary analysis of data from seven treatment studies involving 920 participants. The researchers sought to determine whether decreases in self-reported cannabis use were associated with improvements in cannabis-related problems and functional outcomes, and if so, what percentage decrease in cannabis use is needed for meaningful improvement. The results indicated that reductions in cannabis use falling short of total abstinence were indeed associated with clinically meaningful improvement in cannabis-related problems and functional outcomes.
Key Findings on Cannabis Use Reduction
The exploratory analyses revealed that reductions of approximately 50% in days of use and 75% in use amounts were associated with maximum improvements on the clinician-rated Clinical Global Impressions scale. These findings suggest that achieving substantial reductions in cannabis use, rather than complete abstinence, can lead to tangible benefits for patients.
"As researchers and clinicians work to improve treatment outcomes for persons with substance use disorders, accumulating evidence points toward the benefits of both abstinence and nonabstinence reductions in quantity and frequency of drug use as scientifically justified endpoints," the study authors noted.
Implications for Treatment Development
The study's findings have significant implications for medication development, particularly for cannabis use disorder, where there are currently no FDA-approved medications. The FDA typically requires abstinence outcomes in treatment studies for substance use disorders (other than alcohol use disorder), but this study provides evidence that non-abstinence outcomes can also be clinically meaningful.
To consider outcomes other than total abstinence as the primary endpoint for FDA approval, it is crucial to conduct studies that demonstrate such outcomes are associated with clinically meaningful improvements. This study offers initial evidence that reductions in cannabis use can indeed be beneficial to patients with cannabis use disorder.
The Need for New Approaches
With the increasing rates of cannabis use and use disorders, and the limited availability of effective treatments, a more nuanced understanding of how to achieve therapeutic benefit short of total abstinence is essential. This study represents a step forward in defining the requirements for a meaningful reduction in cannabis use, which can inform future research and treatment strategies.
"The increases in adverse consequences from cannabis use and use disorders and the lack of available treatments highlight the urgency of such work," the authors concluded.
