The purpose of this study is to determine whether extended pretreatment with varenicline (Chantix) is more efficacious for smoking cessation than standard pretreatment, how well varenicline is tolerated in heavy drinking smokers, and whether varenicline reduces alcohol consumption.

Smoking rates are elevated among drinkers compared to non-drinkers (Marks et al., 1997). Moreover, there is some evidence that both smokers who drink alcohol are less successful quitting smoking (Leeman, Huffman, & O'Malley, 2007). Thus, identifying interventions that are effective in reducing both smoking and heavy drinking in this population is warranted. Varenicline, a medication recently approved by the FDA, results in smoking cessation rates as high as 50%, significantly better than bupropion or placebo. There is preliminary experimental evidence from both animal and human laboratory research that varenicline reduces alcohol seeking and consumption (McKee, 2008; Steensland et al., 2007).

The typical dose schedule for varenicline involves a 1 week pretreatment phase prior to quitting smoking (Gonzales et al., 2006; Jorenby et al., 2006; Nides et al., 2006). However, greater quit rates have been observed 1 month after using varenicline compared to 1 week. Therefore, it is possible that extended pretreatment with varenicline may also yield better cessation outcomes than the standard 1 week lead in period. This may be particularly true if pretreatment also reduces alcohol consumption prior to the quit attempt.

Thirty regular smokers who drink alcohol heavily will receive open-label varenicline for 5 weeks according to the recommended titration schedule up to 1mg varenicline twice daily. Prior to the smoking quit date, subjects will be randomized to receive either extended pretreatment with varenicline (titration up to 1mg) for 4 weeks or short-term varenicline pretreatment (3 weeks placebo followed by 1 week of varenicline).

The primary aims of the study are to examine: (a) the efficacy of extended varenicline pretreatment for smoking cessation, (b) the safety and tolerability of varenicline in heavy drinking smokers, and (c) the efficacy of varenicline for reducing alcohol consumption in human participants. Effect size estimates for prolonged smoking abstinence and heavy drinking will be generated for a NIH grant application.

Inclusion Criteria:

1. Between the ages of 18 and 75.
2. Smoking 5 or more cigarettes per occasion at least 3 times per week.
3. Fewer than 3 months of smoking abstinence in the past year.
4. Motivated to stop smoking.
5. Report exceeding maximum weekly drinking limits every week in the past 4 weeks and exceeding maximum daily drinking limits on at least 1 occasion in the past 4 weeks. Weekly heavy drinking is defined as 8 or more drinks for women and 15 or more drinks for men. Daily heavy drinking is defined as 4 or more drinks for women and 5 or more drinks for men on an occasion.

Exclusion Criteria:

1. Exhibit current, clinically significant physical disease or abnormality on the basis of medical history, physical examination, or routine laboratory evaluation
2. Any unexplained elevations in liver enzymes (i.e., transaminases, bilirubin)
3. Clinically significant cardiovascular disease
4. Uncontrolled hypertension
5. Hepatic or renal impairment
6. Severe chronic obstructive pulmonary disease
7. Diabetes mellitus requiring insulin or oral hypoglycemic medications.
8. Baseline systolic blood pressure higher than 150 mm Hg or diastolic blood pressure higher than 95 mm Hg
9. History of cancer (except treated basal cell or squamous cell carcinoma of the skin).
10. History of clinically significant allergic reactions.
11. Exhibit serious psychiatric illness (i.e., schizophrenia, bipolar disorder, severe major depression, panic disorder, borderline personality disorder, organic mood or mental disorders, or substantial suicide or violence risk) by history or psychological examination)
12. Have a current diagnosis of DSM-IV drug dependence other than nicotine or alcohol.
13. Have a current Diagnostic and Statistical Manual Diploma in Social Medicine IV (DSM-IV) diagnosis of alcohol dependence that is clinically severe defined by a) a history of seizures, delirium, or hallucinations during alcohol withdrawal, b) a Clinical Institute Withdrawal Assessment scale (Sullivan et al., 1989) score of > 8, c) report drinking to avoid withdrawal symptoms, or d) have had prior treatment of withdrawal.
14. Use of another investigational drug within 30 days.
15. Intention to donate blood or blood products during the treatment phase of the study.
16. Use of tobacco products other than cigarettes or use of marijuana.
17. Use of nicotine replacement therapy, clonidine, varenicline, bupropion, or nortriptyline within the month prior to enrollment or intention to use medication that might interfere with study medication.
18. Body Mass Index (calculated as weight in kilograms divided by the square of height in meters) less than 15 or greater than 38 or weight less than 45 kg.
19. Females of childbearing potential who are pregnant, nursing, or not practicing effective contraception (oral, injectable, or implantable contraceptives, intrauterine device, or barrier method with spermicide).

Adverse events also assessed post quitting smoking during the open label phase of the study.