Placebo-controlled randomized clinical trial testing the efficacy and safety of varenicline for smokers with HIV

Abstract

Background: People living with HIV/AIDS (PLWH) smoke tobacco at higher rates and have more difficulty quitting than the general population, which contributes to significant life-years lost. The effectiveness of varenicline, one of the most effective tobacco dependence treatments, is understudied in HIV. We evaluated the safety and efficacy of varenicline for smoking cessation among PLWH.

Methods: This was a single-site randomized, double-blind, placebo-controlled, phase 3 clinical trial (NCT01710137). PLWH on antiretroviral therapy (ART) who were treatment-seeking daily smokers were randomized (1:1) to 12 weeks of varenicline (n = 89) or placebo (n = 90). All participants were offered six smoking cessation behavioral counseling sessions. The primary outcome was 7-day point prevalence abstinence, confirmed with breath carbon monoxide, at Weeks 12 and 24. Continuous abstinence and time to relapse were secondary outcomes. Safety measures were treatment-related side effects, adverse events, blood pressure, viral load, and ART adherence.

Results: Of the 179 smokers, 81% were African American, and 68% were male. Varenicline increased cessation at Week 12 (28.1% vs. 12.1%; OR = 4.54, 95% CI:1.83-11.25, P = .001). Continuous abstinence from Week 9 to 12 was higher for varenicline vs. placebo (23.6% vs. 10%; OR = 4.65, 95% CI:1.71-12.67, P = .003); at Week 24, there was no effect of varenicline for point prevalence (14.6% vs. 10%), continuous abstinence (10.1% vs. 6.7%), or time to relapse (Ps > .05). There were no differences between varenicline and placebo on safety measures (Ps > .05).

Conclusions: Varenicline is safe and efficacious for short-term smoking cessation among PLWH and should be used to reduce tobacco-related life-years lost in this population.

Keywords: AIDS; HIV; Nicotine dependence; Smoking cessation; Tobacco use; Varenicline.

Figure 1.

CONSORT Diagram.

Figure 2.

Rates of 7-day point prevalence and continuous abstinence at weeks 12, 18, and 24 across treatment arm. Intent to treat sample (N=179); point prevalence quit rates are 7-day self-reported, carbon monoxide confirmed; continuous abstinence are self-reported cessation from week 9 to the follow-up time-point, confirmed with carbon monoxide at the follow-up assessment time-point. All values are % abstinent. Weeks 12 and 24 were primary outcomes and Week 18 was a secondary end point. ** P<0.001; * P <0.05

Figure 3.

Nausea severity by treatment arm at Weeks 0, 3, 7, and 12. Mean ratings of nausea severity (range: 0=none at all to 3=severe) throughout the trial. Except for a greater increase in nausea between Weeks 0 and 3 in the varenicline group, there were no treatment arm effects at any other timepoint.