Naltrexone and Varenicline: Weight Gain and Tolerability in Cigarette Smokers

Smoking Clinical Trial

Official title: Naltrexone and Varenicline: Weight Gain and Tolerability in Smokers

Status Completed

Clinical Trial Summary

The purpose of this study is to determine whether the combination of naltrexone (Depade) and varenicline (Chantix) minimizes post-smoking cessation weight gain and how well the combination is tolerated.

Clinical Trial Description

Varenicline, a medication recently approved by the FDA, results in smoking cessation rates as high as 50%, significantly better than bupropion or placebo. However, varenicline does not reduce post-cessation weight gain, so weight concerns may keep some smokers from taking advantage of this effective therapy.

A potential solution would be to combine varenicline with an agent that reduces weight gain. In this regard, several studies have shown that naltrexone reduces weight gain (O'Malley et al., 2006; Toll et al., 2007).

This effect appears to be dose dependent, favoring lower doses (i.e., 25 mg daily). Thus, the proposed study seeks to conduct a pilot clinical trial of low dose naltrexone (25 mg daily) compared to placebo for minimizing weight gain in combination with varenicline for smoking cessation. Forty individuals who smoke at least 10 cigarettes per day will receive open-label varenicline for 12 weeks according to the recommended titration schedule up to 1 mg varenicline twice daily. Subjects will be randomized to receive either placebo or 25 mg naltrexone daily, with treatment starting at the quit date (after 1 week on varenicline to minimize nausea, a side effect of both varenicline and naltrexone) and continuing for 11 weeks. Subjects will take 12.5 mg naltrexone daily for the first week and 25 mg naltrexone daily for the next 10 weeks of treatment. In an effort to uncover mechanisms for naltrexone's weight suppressant effects, an experiment will be conducted using food odors and food consumption to examine naltrexone's effects on palatability, incentive value, and alliesthesia.

This experiment will be conducted pretreatment and after 2 weeks on naltrexone. The primary aim of this pilot study is to examine weight gain in participants who complete the clinical trial treatment. Weight gain for those who are continuously abstinent for the last 4 weeks of treatment and rates of adverse events will be secondary outcomes. The effects of naltrexone on odor/food palatability, incentive value, and alliesthesia will be exploratory outcomes. Effect size estimates for weight gain will be generated for a NIH grant application. ;

Related Conditions & MeSH terms

• Nicotine Dependence
• Smoking
• Tobacco Use Disorder
• Weight Gain

• NCT number: NCT00502216
• Study type: Interventional
• Source: Yale University
• Status: Completed
• Phase: Phase 1/Phase 2
• Start date: July 2007
• Completion date: June 2009