Smoking cessation drug, varenicline, could help treat cannabis use disorder (CUD) in men. The corresponding study was published in Addiction.
CUD is becoming increasingly common as legislation and societal attitudes around cannabis change. Current pharmacological treatments for the condition, however, remain limited. Early evidence from preclinical studies and a proof-of-concept randomized controlled trial indicate that varenicline could help treat the condition. In the current study, researchers set out to extend these findings.
To do so, they conducted a phase 2, randomized, placebo-controlled trial including 174 participants with CUD who used cannabis at least three days per week. They were randomized to receive either varenicline, working up to 1 mg twice per day, or a placebo, for 12 weeks. Participants also underwent weekly brief medical management sessions to encourage adherence to their treatment plan.
Ultimately, men receiving varenicline used cannabis fewer times per week than men on the placebo. Whereas the varenicline group averaged 7.9 cannabis sessions per week during the study and 5.7 sessions following, those on the placebo used cannabis more than 12 times per week. While males used cannabis for an average of 3.8 days per week, those on the placebo used the substance 4.7 days per week.
The effects did not extend to women; those on varenicline experienced no significant difference in cannabis use compared to those on the placebo. Women taking varenicline showed higher withdrawal and craving scores as well as higher anxiety scores than other groups. Perhaps as a consequence, they reported lower medication adherence than those taking a placebo.
“Our study found that varenicline, a drug that helps people to reduce or stop smoking, may be effective at reducing cannabis use as well, but only for men,” said lead author, Aimee McRae-Clark, Professor at the Department of Psychiatry and Behavioral Sciences at the Medical University of South Carolina, in a press release.
“Our next step is to further explore varenicline for cannabis use disorder, using a larger sample size of women, to better understand this sex difference in the treatment outcome. In the meantime, we are encouraged that varenicline shows potential promise in treating this fast-growing problem,” she added.
Sources: EurekAlert, Addiction