Effectiveness of Using Reduced Nicotine Cigarettes in Men and Women Smokers to Combat Nicotine Addiction

Safety of Nicotine Reduction Strategy

This is a 2-year study involving the progressive reduction in the nicotine content of cigarettes. The investigators believe that at the end of the study smokers of cigarettes with progressively reduced nicotine content will be "weaned" from nicotine. At the end of the study, the result will be a decreased level of nicotine dependence. When smokers are again free to choose any smoking behavior, they will smoke fewer cigarettes and/or have a greater interest in quitting compared to a control group that smokes their usual cigarettes.

Study Overview

• Status: Completed
• Conditions: Tobacco Use Disorder; Nicotine Dependence

Detailed Description

This is a 2-year, randomized, two-arm study involving a 6-month period of progressive reduction in the nicotine content of cigarettes. During the first year (tapering/maintenance phases), subjects will smoke progressively reduced nicotine content (RNC) cigarettes over a period of six months, and then remain on the lowest nicotine content cigarette for an additional six months. Comparisons will be made with a control group in which subjects will smoke their usual normal nicotine yield cigarettes. There will be a one year follow-up phase during which subjects will be monitored and will be free to resume smoking a commercial cigarette of their choice, or to quit.

We hypothesize that smokers of cigarettes with progressively reduced nicotine content will experience a reduction in nicotine intake without compensatory oversmoking. This will serve to "wean" them from nicotine and result in a decreased level of nicotine dependence. Once this has occurred, subjects will then be able to maintain their reduced level of nicotine intake for the 6 months that they continue smoking the lowest level RNC cigarette. When they are again free to choose any smoking behavior (follow-up phase), as a result of the period of lowered dependence they will smoke fewer cigarettes and/or have a greater interest in quitting compared to the control group, whose level of nicotine dependence is hypothesized to be sustained throughout.

Primary Hypotheses:

1. Nicotine intake will be lower for the RNC group than for the control group.
2. Exposure to tobacco smoke gas phase constituents will be similar for the RNC and control group.
3. Exposure to tobacco smoke tar constituents will be similar for the RNC and control group.
4. Cardiovascular biomarkers of inflammation, platelet activation, endothelial dysfunction, and HDL cholesterol will be lower for the RNC group than for the control group.
5. Cigarette consumption, as measured by cigarettes-per-day (CPD), will be lower for the RNC group than for the control group.

Secondary hypotheses:

1. Over the course of tapering and maintenance and at follow-up, interest in quitting will be higher in the RNC group compared to the control group.
2. At follow-up, measures of cigarette consumption, nicotine intake, and exposure to tobacco smoke combustion constituents will be lower for the RNC group compared to the control group.

• Study Type: Observational
• Enrollment (Actual): 135

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94110
      • University of California, San Francisco

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Health adults 18 and over

Description

Inclusion Criteria:

• Healthy on the basis of medical history and screening blood tests

• Current moderate-to-heavy smoker as determined by:

  1. smoking more than 10 cigarettes per day regularly for the past year (by history); and
  2. expired carbon monoxide (CO) at screening visit of 25 ppm or more and/or plasma cotinine level of 100 ng/ml or more.
• Age 18-70 years
• Any racial/ethnic background

Exclusion Criteria:

• Expressed desire to quit smoking within 6 months.
• Significant medical conditions (such as anemia, heart disease, uncontrolled hypertension, thyroid disease, diabetes, renal or liver impairment, glaucoma, or prostatic hypertrophy) or psychiatric condition (such as current major depression, history of schizophrenia or bipolar disorder, or current regular use of psychiatric medications such as major tranquilizers and antidepressants). Smokers with uncomplicated controlled hypertension may be enrolled.
• Pregnancy or lactation (by history)
• Current use of smokeless tobacco, pipes or cigars
• Alcohol abuse or illicit drug use (by history)
• Concurrent participation in another clinical trial or prior participation in our pilot studies using the same RNC cigarettes as in these studies

Study Plan

How is the study designed?

Collaborators and Investigators

• Sponsor: University of California, San Francisco

Publications and helpful links

General Publications

• Hukkanen J, Jacob P 3rd, Benowitz NL. Metabolism and disposition kinetics of nicotine. Pharmacol Rev. 2005 Mar;57(1):79-115. doi: 10.1124/pr.57.1.3.
• Benowitz NL, Jacob P 3rd, Bernert JT, Wilson M, Wang L, Allen F, Dempsey D. Carcinogen exposure during short-term switching from regular to "light" cigarettes. Cancer Epidemiol Biomarkers Prev. 2005 Jun;14(6):1376-83. doi: 10.1158/1055-9965.EPI-04-0667.
• Gray N, Henningfield JE, Benowitz NL, Connolly GN, Dresler C, Fagerstrom K, Jarvis MJ, Boyle P. Toward a comprehensive long term nicotine policy. Tob Control. 2005 Jun;14(3):161-5. doi: 10.1136/tc.2004.010272.
• Arcavi L, Benowitz NL. Cigarette smoking and infection. Arch Intern Med. 2004 Nov 8;164(20):2206-16. doi: 10.1001/archinte.164.20.2206.
• Swan GE, Benowitz NL, Jacob P 3rd, Lessov CN, Tyndale RF, Wilhelmsen K, Krasnow RE, McElroy MR, Moore SE, Wambach M. Pharmacogenetics of nicotine metabolism in twins: methods and procedures. Twin Res. 2004 Oct;7(5):435-48. doi: 10.1375/1369052042335269.
• Benowitz NL, Gan Q, Goniewicz ML, Lu W, Xu J, Li X, Jacob P 3rd, Glantz S. Different profiles of carcinogen exposure in Chinese compared with US cigarette smokers. Tob Control. 2015 Dec;24(e4):e258-63. doi: 10.1136/tobaccocontrol-2014-051945. Epub 2014 Dec 22.

Helpful Links

• UCSF Nicotine and Tobacco Research

Study record dates

Study Major Dates

• Study Start: July 1, 2005
• Primary Completion (Actual): March 1, 2010
• Study Completion (Actual): July 1, 2010

Study Registration Dates

• First Submitted: December 9, 2005
• First Submitted That Met QC Criteria: December 9, 2005
• First Posted (Estimate): December 12, 2005

Study Record Updates

• Last Update Posted (Estimate): May 23, 2013
• Last Update Submitted That Met QC Criteria: May 21, 2013
• Last Verified: May 1, 2013

More Information

Terms related to this study

• Keywords: Smoking; Tobacco; Nicotine
• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders; Tobacco Use Disorder
• Other Study ID Numbers: R01CA078603-05A1 (U.S. NIH Grant/Contract)