St. John's Wort for Tobacco Cessation
Cigarette smoking is the single most important preventable cause of morbidity, mortality and
excess health care costs in the United States. The prevalence of cigarette smoking among
U.S. adults has declined from 42% in 1965 to 20.9% in 2004. However, the overall decline is
not occurring at a rate that will meet national health objectives by 2010. Available
pharmacotherapies for the treatment of tobacco dependence are not efficacious for all
tobacco users and have an overall estimated efficacy of approximately 20% for long-term
tobacco cessation. Thus, novel pharmacotherapies for tobacco cessation need to be explored.
Current smokers tend to be younger with less education and belong to a lower socioeconomic
status. Tobacco cessation treatments are expensive and often not covered by Medicare,
Medicaid, or third party-payers. Our goal is to evaluate novel, safe, acceptable, effective,
and inexpensive therapies that will increase tobacco abstinence rates.
The United States Public Health Service (USPHS) guideline recommends nicotine replacement
therapy and bupropion as first-line agents for the treatment of tobacco dependence.
Bupropion acts by central dopamine and norepinephrine reuptake inhibition. St. John's Wort
(SJW), a widely used herbal product to treat mild to moderate depression, shares a similar
mechanism of action and is available as a tobacco cessation aid in a number of
over-the-counter preparations. While currently approved pharmacotherapies for tobacco
dependence cost between $120-$240 per month, SJW is relatively inexpensive ($15 per month)
and is well-tolerated. At present, no randomized prospective study of St. John's Wort for
tobacco cessation has been published.
We plan to test the efficacy of SJW for tobacco cessation in a randomized, double-blind,
placebo-controlled, three-arm, parallel group, dose-ranging clinical trial. We will obtain
preliminary data about the efficacy of two different oral doses of SJW for improving tobacco
abstinence rates and decreasing symptoms of nicotine withdrawal. All subjects will receive
a behavioral intervention during participation in the study. A total of 120 subjects will
be recruited into the study and randomly allocated to one of the three groups (groups A, B,
and C). Participants in group A will receive SJW 300-mg three times a day for twelve weeks
while participants in group B will receive SJW 600-mg three times a day for twelve weeks.
Participants in group C will receive a matching placebo for the same duration.
We will conduct this research through the Nicotine Research Program (NRP) at the Mayo Clinic
in Rochester, Minnesota. We are uniquely situated for completing this research as more than
7,500 patients have been enrolled in over 75 clinical trials conducted through the NRP. We
propose the following specific aims:
Primary Aims:
1. To obtain preliminary evidence of the effect of a 12-week course of SJW in two different
oral doses of 300-mg three times a day or 600-mg three times a day compared to placebo on
the 7-day point prevalence tobacco abstinence rates at end of treatment and six months in
120 smokers.
Hypothesis: Cigarette smokers who receive SJW in two different oral doses of 300-mg three
times a day or 600-mg three times a day for 12 weeks will have higher 7-day point prevalence
tobacco abstinence rates at end of treatment and six months compared to cigarette smokers
receiving placebo.
Secondary Aim:
1. To obtain preliminary estimates of the effect of a 12-week course of SJW in two
different oral doses of 300-mg three times a day or 600-mg three times a day compared to
placebo on prolonged tobacco abstinence rates at six months.
Hypothesis: Cigarette smokers who receive SJW in two different oral doses of 300-mg three
times a day or 600-mg three times a day for 12-weeks will have higher prolonged tobacco
abstinence rates at six months compared to cigarette smokers receiving placebo.
This study is innovative in that we are testing a novel therapeutic agent for the treatment
of tobacco use. At the completion of this study, we expect to have obtained preliminary
evidence regarding the effect of two different doses of SJW on symptoms of nicotine
withdrawal and tobacco abstinence. We will also collect information on adverse effects of
SJW in tobacco users and obtain data to plan a larger Phase III clinical trial, if the
results from this trial suggest a potential for efficacy.
Interventional
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment
Biochemically Confirmed 7-day Point Prevalence Abstinence From Tobacco
Point prevalence tobacco abstinence was adjudicated if the following conditions were met:(a) self-reported tobacco abstinence for the previous 7 days with a negative response to the question "Have you used any type of tobacco,even a puff, in the past 7 days?" and (b) Expired Carbon Monoxide equal or less then 8 parts per million.
12 weeks following start of medication
No
Amit Sood, M.D., MSc
Principal Investigator
Mayo Clinic
United States: Food and Drug Administration
06-002296
NCT00405912
September 2005
March 2008
Name | Location |
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Mayo Clinic | Rochester, Minnesota 55905 |