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Zyban as an Effective Smoking Cessation Aid for Patients Following an Acute Coronary Syndrome: The ZESCA Trial

Zyban as an Effective Smoking Cessation Aid for Patients Following an Acute Coronary Syndrome: The ZESCA Trial

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00689611
Acronym
ZESCA
Enrollment
392
Registered
2008-06-03
Start date
2005-12-31
Completion date
2010-06-30
Last updated
2015-04-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Acute Coronary Syndrome, Myocardial Infarction, Smoking

Keywords

Acute coronary syndrome, Myocardial infarction, Smoking cessation, Zyban, Secondary intervention post-ACS

Brief summary

Patients who continue to smoke after a heart attack have a 35% increased risk of a recurrent event or death compared with those who quit. Many patients attempt to stop smoking after a heart attack, but relapse rates approach 66%. A variety of smoking cessation aids have been shown to be effective for the general population. However, bupropion is the only non-nicotine replacement therapy shown to improve abstinence rates in healthy young smokers. Furthermore, nicotine replacement therapies (NRTs) are contraindicated in the immediate period following a heart attack because of the undesirable effects of nicotine. Although bupropion has been successfully used to reduce smoking rates in healthy young populations, its efficacy and safety in the setting of patients recovering from an ACS is unknown. These patients, if they continue to smoke, are at exceptionally high risk for recurrent cardiac events. If bupropion is effective in this population, it will have a major impact on secondary prevention of recurrent clinical events in patients who suffer a heart attack.

Detailed description

Patients who continue smoking after ACS have a 35% increased risk of reinfarction or death compared with those who quit. Many patients attempt to stop smoking after an acute coronary syndrome (ACS), but relapse rates approach 66%. A variety of smoking cessation aids have been shown to be effective for the general population. However, physicians are reluctant to use a nicotine-based therapy because of its hemodynamic effects. Bupropion is the only non-nicotine replacement therapy shown to improve abstinence rates in healthy young smokers by approximately 50%. Although bupropion has successfully been used to reduce smoking rates in healthy young populations, its efficacy and safety in the setting of patients recovering from an ACS is unknown. The ZESCA Trial will directly compare the efficacy and safety of bupropion versus placebo as a means of reducing smoking rates in patients following an ACS. The ZESCA Trial will be a multi-center effort, coordinated from the Jewish General Hospital/McGill University (Montreal, Quebec). A total of 1500 patients will be randomized following an ACS but before hospital discharge via an Internet web site. Prior to the start of the treatment, patients in both treatment arms will receive a standard physician-administered counseling session regarding smoking cessation. Patients will begin treatment in-hospital and will be monitored in-hospital for ≥ 2 days prior to discharge. Half the patients will receive bupropion for 9 weeks and the other half will receive placebo pills for 9 weeks. Patients receiving bupropion will take 150 mg once per day for 3 days and then 150 mg twice per day for the remainder of 9 weeks. Prior to discharge, the patients will receive an information sheet listing the possible side effects of bupropion. They will be advised to consult the treating physician should they experience any listed side effects. While in-hospital, patients will have quit smoking and they will be instructed to not restart smoking when discharged. Phone calls to the patients will be made by the study nurses at weeks 1 and 2 of the 9-week treatment period. In addition, the patients will have clinic visits at weeks 4 and 9 as well as months 6 and 12. Smoking abstinence will be assessed at 4 weeks, 9 weeks, 6 months, and 12 months after randomization. Smoking abstinence will be defined as the complete abstinence in the week prior to the clinic visits and levels of exhaled carbon monoxide ≤ 10 ppm. Side effects of bupropion in patients following ACS as well as clinical events following initiation of treatment will be measured at weeks 1-8 (by telephone calls), and weeks 4 and 9 as well as months 6 and 12 (by clinic visits). Withdrawal symptoms will also be assessed by the nurses during their weekly calls. Trials previously conducted with bupropion involved young healthy smokers. The ZESCA trial will be the first to examine the utility of bupropion in a group of patients with an ACS. These patients, if they continue to smoke, are at exceptionally high risk for recurrent cardiac events. If bupropion is effective in this population, it will have a major impact on secondary prevention of recurrent clinical events in patients who suffer an ACS.

Interventions

DRUGBupropion HCl ER

150 mg tablets po qd for 3 days and then 150 mg po bid for remainder of 9 weeks

DRUGPlacebo

Placebo

Sponsors

Canadian Institutes of Health Research (CIHR)
CollaboratorOTHER_GOV
Heart and Stroke Foundation of Canada
CollaboratorOTHER
Mark Eisenberg
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* ≥ 18 years of age * Smoke at least 10 cigarettes/day for the past year * Suffered an enzyme-positive ACS * Planned hospitalization of ≥24 hours * Motivated to quit smoking * Likely to be available for follow-up * Able to understand and read English or French

Exclusion criteria

* Medical condition with a prognosis of \< 1 year * Pregnant or lactating * Current use of Wellbutrin or any other medications that contain bupropion * Current use of any medical therapy for smoking cessation (e.g. BuSpar, fluoxetine, doxepin, nicotine gum, or nicotine patch) * Current seizure disorder, history of seizures or predisposition to seizures (e.g. history of brain tumor, severe head trauma, or stroke) * History of bulimia or anorexia nervosa * Current diagnosis of major depression (requiring medication), bipolar disease, or dementia * History of suicidal events (previous suicide attempt, suicidal ideation) or family history of suicide * Diagnosed hepatic failure, cirrhosis, hepatitis or history of hepatic impairment (AST or ALT levels ≥ 2 times upper limit of normal prior to admission for ACS) * Renal impairment with creatinine levels ≥ 2 times the upper limit of normal * Excessive alcohol consumption defined as ≥ 14 alcoholic drinks per week * Use of any illegal drugs in the past year (e.g. cocaine, heroin, opiates) * Current use of medications that lower seizure threshold e.g. amantadine, anti-depressants, anti-malarials, anti-psychotics, levodopa, lithium, quinolone antibiotics, ritonavir, systemic steroids, theophyllin, type 1C antiarrhythmics (e.g. encainide, flecainide, propafenone) * Use of MAO inhibitors or thioridazine in the past 15 days * Current use of over-the-counter stimulants (e.g. ephedrine, phenylephrine) or anoretics

Design outcomes

Primary

MeasureTime frameDescription
Smoking Abstinence12 monthsThe primary end point was 7-day point prevalence smoking abstinence at 12 months. Smoking cessation was defined as self-reported abstinence in the week before the 12-month clinic visit and a measurement of exhaled carbon monoxide less than 11 ppm. The primary end point was analyzed on an intention-to-treat (ITT) basis. Our ITT analysis assumed that those who withdrew consent or were lost to follow-up had returned to smoking at their baseline rates. This assumption is common in smoking cessation trials.

Secondary

MeasureTime frameDescription
Composite Major Adverse Cardiovascular Events (MACE)12 monthsAll clinical end points were adjudicated by members of the Endpoints Evaluation Committee who were blinded to treatment assignment. Composite MACE (death, myocardial infarction, unstable angina)

Countries

Bangladesh, Canada, India, Iran, Pakistan, Tunisia, United States

Participant flow

Participants by arm

ArmCount
Placebo
participants received placebo for 9 weeks. Placebo: Placebo
200
Bupropion
participants received bupropion for 9 weeks. Bupropion HCl ER: 150 mg tablets po qd for 3 days and then 150 mg po bid for remainder of 9 weeks
192
Total392

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyDeath69
Overall StudyLost to Follow-up2728
Overall StudyWithdrawal by Subject89

Baseline characteristics

CharacteristicBupropionPlaceboTotal
Age, Continuous54.5 years
STANDARD_DEVIATION 10.4
53.4 years
STANDARD_DEVIATION 10.3
53.9 years
STANDARD_DEVIATION 10.3
Cardiac catheterization during index admission128 participants136 participants264 participants
Coronary artery bypass graft during index admission10 participants15 participants25 participants
Index admission was for ST-segment elevation myocardial infarction [STEMI]121 participants133 participants254 participants
No. of cigarettes/day (past year)23.2 cigarettes/day
STANDARD_DEVIATION 10.8
23.2 cigarettes/day
STANDARD_DEVIATION 10.4
23.2 cigarettes/day
STANDARD_DEVIATION 10.6
No. of years smoked33.2 years
STANDARD_DEVIATION 13
32.6 years
STANDARD_DEVIATION 11.9
32.9 years
STANDARD_DEVIATION 12.4
Percutaneous coronary intervention during index admission93 participants104 participants197 participants
Region of Enrollment
Canada
96 participants101 participants197 participants
Region of Enrollment
India
10 participants9 participants19 participants
Region of Enrollment
Iran, Islamic Republic of
31 participants31 participants62 participants
Region of Enrollment
Pakistan
18 participants18 participants36 participants
Region of Enrollment
Tunisia
4 participants6 participants10 participants
Region of Enrollment
United States
33 participants35 participants68 participants
Sex: Female, Male
Female
31 Participants34 Participants65 Participants
Sex: Female, Male
Male
161 Participants166 Participants327 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
48 / 20058 / 192
serious
Total, serious adverse events
37 / 20034 / 192

Outcome results

Primary

Smoking Abstinence

The primary end point was 7-day point prevalence smoking abstinence at 12 months. Smoking cessation was defined as self-reported abstinence in the week before the 12-month clinic visit and a measurement of exhaled carbon monoxide less than 11 ppm. The primary end point was analyzed on an intention-to-treat (ITT) basis. Our ITT analysis assumed that those who withdrew consent or were lost to follow-up had returned to smoking at their baseline rates. This assumption is common in smoking cessation trials.

Time frame: 12 months

ArmMeasureValue (NUMBER)
PlaceboSmoking Abstinence32.0 percentage of participants
BupropionSmoking Abstinence37.2 percentage of participants
Secondary

Composite Major Adverse Cardiovascular Events (MACE)

All clinical end points were adjudicated by members of the Endpoints Evaluation Committee who were blinded to treatment assignment. Composite MACE (death, myocardial infarction, unstable angina)

Time frame: 12 months

ArmMeasureValue (NUMBER)
PlaceboComposite Major Adverse Cardiovascular Events (MACE)11.0 percentage of participants
BupropionComposite Major Adverse Cardiovascular Events (MACE)13.0 percentage of participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026