Varenicline/naltrexone combination may improve drinking outcomes in heavy-drinking smokers

Concomitant targeting of smoking cessation and drinking reduction via pharmacotherapy appeared feasible, according to results of a randomized clinical trial published in American Journal of Psychiatry.

“[Prior study] findings suggested that a clinical trial of the combination of varenicline and naltrexone for heavy-drinking smokers was warranted,” Lara A. Ray, PhD, of the department of psychiatry and biobehavioral sciences at the University of California, Los Angeles, and colleagues wrote. “Combination pharmacotherapy for addiction is an understudied area, with potential to reach additive or even synergistic effects on craving and substance use. Further, the concurrent treatment of smoking and heavy alcohol use holds great promise for patients and health care systems alike.”

In the current superiority trial, the researchers compared the combination of varenicline and naltrexone with varenicline alone for smoking cessation and drinking reduction among 165 daily smokers who drank heavily. For 12 weeks, participants received either 2 mg per day of varenicline plus 50 mg per day of naltrexone or 2 mg per day of varenicline plus matched placebo pills. As primary outcomes, the researchers used 7-day point prevalence of nicotine abstinence at 26 weeks of follow-up and number of drinks per drinking day during the 12 weeks of the treatment phase.

Results showed significantly higher smoking abstinence at 26 weeks among the varenicline plus placebo group (45.1%) compared with the varenicline plus naltrexone group (26.5%). The researchers observed a medication effect that favored the combination of varenicline and naltrexone over varenicline alone across the 12 weeks of the treatment phase for drinks per drinking day; however, it did not meet the significance threshold.

“These results suggest that smoking cessation and drinking reduction can be targeted concomitantly and that while varenicline alone may be sufficient as a smoking cessation aid in heavy-drinking smokers, the combination of varenicline and naltrexone may confer unique benefits with regard to drinking outcomes but not smoking cessation,” Ray and colleagues wrote.