Beyond "Safe and Effective": The urgent need for high-impact smoking cessation medications

Smoking cessation medications (SCMs) are an evidence-based cornerstone of comprehensive tobacco control programs globally. However, the impact of SCMs on population smoking prevalence is controversial, with inconsistencies between randomized controlled trials (RCTs) and population-based observational studies. We estimated SCM impact on permanent cessation and population smoking prevalence by extrapolating efficacy estimates from meta-analyses of RCTs, using the standard population impact formula: efficacy*reach. We calculated the potential SCM impact under a range of assumptions for permanent cessation (20%,14%), behavioral support (yes/no), reach (40%-2%), and underlying smoking prevalence. Assuming behavioral support for all, depending on reach, 8%-0.3% of smokers are expected to quit permanently. Without behavioral support, permanent cessation is estimated to be 6.4%-0.2%. Assuming an underlying population smoking prevalence of 14%, (current U.S. prevalence), the maximum impact on population smoking prevalence is 1.12%. Impact on prevalence increases with increasing underlying country-specific levels of prevalence. With current U.S. levels of reach, behavioral support and smoking prevalence, we estimate that, based on a single course of treatment, 2.3% of smokers would quit permanently, contributing to a 0.3% decrease in population level smoking prevalence. Even under ideal conditions, the potential of current first-line SCMs to increase cessation in a substantial proportion of smokers, and reduce population smoking prevalence, is limited. In order to avert the predicted billion tobacco-caused deaths in this century, "safe and effective" medications are not sufficient: SCMs with high population impact are urgently needed. Policies to ensure the availability and accessibility of highly efficacious SCMs, with behavioral support, are crucial.