Tobacco smoking remains the leading cause of preventable disease and death in the United States, accounting for more than 480,000 deaths annually.1 An estimated 50.6 million US adults (20.8%) identify as tobacco users, with even higher rates among veterans (29.2%).2,3 Tobacco use is estimated to cost the US more than $300 billion annually in direct and indirect medical costs.4 According to a 2015 report, more than two-thirds of adult smokers reported a desire to quit, while only 7.5% reported successfully quitting in the past year.5 According to that same report, only 57.2% of smokers who had seen a health professional in the past year reported receiving advice to quit.5 This statistic is unfortunate, as interventions that combine behavioral and pharmacologic support can drastically increase tobacco cessation rates compared with self-help materials or no treatment.6
Currently, 7 first-line medications (5 nicotine, 2 nonnicotine) have been shown to increase long-term smoking abstinence rates. Varenicline was approved by the US Food and Drug Administration (FDA) in 2006 for use in adults as an aid to smoking cessation treatment. As a partial agonist of the α4β2 nicotinic acetylcholine receptor, varenicline’s mechanism of action is believed to involve reduction of nicotine’s rewarding capacity.7 Varenicline not only aids in complete tobacco cessation but also has been found to be effective for reducing cigarette consumption among smokers not yet willing or able to make a quit attempt.8 Furthermore, varenicline has demonstrated efficacy among users of smokeless tobacco in achieving continuous abstinence.9
Widespread adoption of varenicline into clinical practice was perhaps slowed by early concerns of psychiatric complications, prompting the FDA to issue a boxed warning for risk of serious neuropsychiatric events. This boxed warning was removed in 2016 in response to publication of the Evaluating Adverse Events in a Global Smoking Cessation Study (EAGLES). In this randomized controlled trial of more than 8000 participants, among whom 50.5% had a psychiatric disorder determined to be stable, varenicline significantly increased rates of continuous tobacco cessation compared with bupropion or the nicotine patch without an increased risk of neuropsychiatric events.10 This study underscored not only the safety of varenicline, but also its superiority over other first-line cessation products. The most recently published clinical practice guidelines recommend varenicline as a first-line agent for helping patients achieve long-term smoking cessation.11,12
Pharmacists are uniquely positioned to provide tobacco cessation interventions given their medication expertise and accessibility to the public. Indeed, multiple studies have demonstrated the effectiveness of pharmacist-led interventions on tobacco cessation.13-15 As of 2019, only 12 states had statutes or regulations addressing pharmacist prescribing of tobacco cessation aids without a collaborative practice agreement or local standing order.16 Until recently, most of these states limited pharmacists’ prescriptive authority to nicotine replacement therapy (NRT). New Mexico serves as the outlier, as pharmacists have been authorized to prescribe all FDA-approved tobacco cessation products since 2004. A 2014 New Mexico study consisting of > 1400 patients showed that pharmacist-provided tobacco cessation interventions, which included management of varenicline, resulted in quit rates similar to those seen with management by other health care professionals.17 Aside from this study, there is a paucity of data available to assess the impact of pharmacist management of varenicline, let alone provide a head-to-head comparison with management by other clinicians.
Within the US Department of Veterans Affairs (VA), the clinical pharmacy specialist (CPS) is credentialed as an advanced practitioner with authority to independently manage patient medication therapy for a variety of diseases specified under a scope of practice. Although CPSs have provided tobacco cessation services for years, expansion of their scope to include varenicline did not occur until June 26, 2019, at the Southern Arizona VA Health Care System (SAVAHCS). All VA prescribers must follow the same criteria for prescribing varenicline. Unless previously trialed on varenicline, patients must have failed an appropriate trial of first-line agents (NRT, bupropion, or combination therapy) or have a contraindication to use of these first-line therapies before varenicline can be considered. Exclusions to therapy would include history of serious hypersensitivity to varenicline; suicidal intent, plan, or attempt within the past 12 months; current substance use disorder other than nicotine (unless varenicline recommended or prescribed by mental health professional); or unstable mental health disorder.18
The purpose of this study was to evaluate the efficacy and safety of CPS management of varenicline compared with other clinicians. We hope that this study provides insight regarding how the expansion of CPS scope to include prescriptive authority for varenicline has affected patient outcomes.