In the United States, approximately 7.7 million individuals older than 12 years of age report current (past month) use of smokeless tobacco (ST). ST use has been associated with oral and extra-oral cancer as well as cardiovascular and cerebrovascular disease. To date, no pharmacotherapies have been shown to increase long-term (e 6 months) abstinence rates in ST users. Novel pharmacotherapies that decrease withdrawal symptoms and nicotine self-administration need to be tested in ST users. Varenicline (Chantix"""""""", Pfizer) is a novel selective nicotinic receptor partial agonist with specificity for the 1422 nicotine acetylcholine receptor that has demonstrated remarkable efficacy for increasing long-term tobacco abstinence rates in cigarette smokers. The novel mechanism of action of varenicline potentially circumvents the limitations of using nicotine replacement therapy or bupropion pharmacotherapy in ST users. The overall goal of this line of research is to develop effective pharmacologic treatments for ST users to increase long-term (e 6 months) abstinence rates. The central hypothesis of this application is that varenicline is efficacious for the treatment of ST users. To evaluate this hypothesis, we will conduct a pilot study to obtain preliminary estimates of efficacy of 12-weeks of varenicline for increasing the prolonged and point prevalence tobacco abstinence rates at 12 weeks (end-of- treatment) in ST users. We will also evaluate the effect of varenicline on nicotine withdrawal symptoms and tobacco craving. If the results are promising, we will plan for a multicenter, randomized, double-blinded, placebo-controlled clinical trial with the Oregon Research Institute in Eugene, OR, to investigate the efficacy of varenicline to increase long-term (e 6 months) abstinence rates in ST users.

Public Health Relevance

Smokeless tobacco (i.e., """"""""chew"""""""") use is associated with negative health effects. To date, no medications have been shown to help chewers quit long-term. Varenicline is a new drug that may help. If found to be effective, chewers may take this medication to help them quit and reduce their risk for negative health effects.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21CA132621-02
Application #
7752798
Study Section
Biobehavioral Regulation, Learning and Ethology Study Section (BRLE)
Program Officer
Hunt, Yvonne M
Project Start
2009-01-01
Project End
2010-12-31
Budget Start
2010-01-01
Budget End
2010-12-31
Support Year
2
Fiscal Year
2010
Total Cost
$166,210
Indirect Cost
Name
Mayo Clinic, Rochester
Department
Type
DUNS #
006471700
City
Rochester
State
MN
Country
United States
Zip Code
55905
Ebbert, Jon O; Croghan, Ivana T; Severson, Herbert H et al. (2011) A pilot study of the efficacy of varenicline for the treatment of smokeless tobacco users in Midwestern United States. Nicotine Tob Res 13:820-6
Ebbert, Jon O; Croghan, Ivana T; North, Frederick et al. (2010) A pilot study to assess smokeless tobacco use reduction with varenicline. Nicotine Tob Res 12:1037-40
Ebbert, Jon O; Wyatt, Kirk D; Zirakzadeh, Ali et al. (2009) Clinical utility of varenicline for smokers with medical and psychiatric comorbidity. Int J Chron Obstruct Pulmon Dis 4:421-30
Hurt, Richard D; Ebbert, Jon O; Hays, J Taylor et al. (2009) Treating tobacco dependence in a medical setting. CA Cancer J Clin 59:314-26