Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Phase 4, Multi-National, Randomized, Double-Blind, Placebo-Controlled Study To Evaluate The Efficacy And Safety Of Varenicline Compared To Placebo For Smoking Cessation Through Reduction
Brief Summary: This study will determine whether varenicline is safe and helps people to quit smoking through reduction when they are not willing/able to make an abrupt quit attempt.


Options:
A: Inclusion Criteria:

* Stable on methadone maintenance (an individual is considered 'stable' if they have had a 4 week constant/fixed dose of methadone by self report and verified by B.C. Pharmanet review)
* Subjects must have smoked at least 10 cigarettes per day during the past year and over the month prior to the screening visit, with no period of abstinence greater than 3 months in the past year
* Ages 19 to 75 years (inclusive) and motivated to quit smoking
* Should read and understand English
* For female subjects:

  * instructed and agrees to avoid pregnancy through 30 days after the last dose of study medication
  * has a negative urine pregnancy test at screening
  * agrees to use birth control method(s) for duration of the study
* Should be available by telephone

Exclusion Criteria:

* Subjects who have used varenicline previously or are currently on other Nicotine Replacement Therapy or pharmacotherapy for smoking cessation (e.g., nicotine patch, zyban or wellbutrin)
* Subjects who have a prior or current history of depression, bipolar affective disorder or a prior or current history of psychotic episodes or suicidal ideation (on the basis of self-report augmented by medical chart review where appropriate and/or corroborating history with previous or current health care provider)
* Subjects who have not reached a stable dose of methadone in their methadone maintenance therapy (4 weeks at a constant/fixed dose of methadone by self-report and verified by B.C. Pharmanet review)
* Pregnancy or currently nursing
B: Inclusion Criteria:

* Smokers seeking treatment
* Aged 18 and over
* Consenting to take part in the trial

Exclusion Criteria:

* Pregnant or breastfeeding
* End-stage renal disease
* Used varenicline in the past 6 months
* Unable to fill in questionnaires in English
* Current psychiatric illness
* Current serious illness including uncontrolled hypertension and recent cardiac event
* Sensitivity to varenicline currently enrolled in other research projects.
C: Inclusion Criteria:

* Male and female cigarette smokers over the age of 18 years who are not willing/able to quit smoking within the next month but who are willing to attempt to reduce their smoking to work toward a quit attempt within the next 3 months.
* Subjects must have smoked an average of at least 10 cigarettes per day during the past year and during the month prior to the screening visit, with no continuous period of abstinence greater than 3 months in the past year and who have an exhaled carbon monoxide (CO) \>10 ppm at screening.
* Subjects with mild to moderate depression or anxiety may be included if their condition is stable.

Exclusion Criteria:

* Subjects with a history of a suicide attempt or any suicidal behavior in the past two years.
* Subjects with severe depression or anxiety.
* Subjects with psychosis, panic disorder, bipolar disorder, post traumatic stress disorder (PTSD), or schizophrenia.
* Subjects with alcohol or substance abuse or dependence (except nicotine) unless in full remission for at least 12 months.
D: Inclusion Criteria:

1. be male or female, 18 years of age or older
2. be able to understand the study, and having understood, provide written informed consent in English
3. have been enrolled in the University of Cincinnati Physicians Company-Opioid Treatment Program (UCPC-OTP) program for at least 30 days and be stable on the current methadone dose for at least 1 week
4. have smoked cigarettes for at least 3 months, have a measured exhaled carbon monoxide (CO) level \> 8 parts per million (ppm), and not planning to seek smoking-cessation treatment within the next 3 months
5. have a willingness to comply with all study procedures, including trying to stop smoking during designated weeks, and to comply with medication instructions
6. based on a week of Quitbit cigarette lighter assessments, with at least 5 days of usable data, smoke ≥ 10 cigarettes/day and smoke at least 30% of daily cigarettes within the 4-hour post-methadone-dosing period
7. if female and of child bearing potential, agree to use one of the following methods of birth control: oral contraceptives, contraceptive patch, barrier (diaphragm or condom), intrauterine contraceptive system, levonorgestrel implant, medroxyprogesterone acetate contraceptive injection,complete abstinence from sexual intercourse, hormonal vaginal contraceptive ring.

Exclusion Criteria:

1. have a current or past diagnosis of any psychotic disorder, or bipolar I or II disorder
2. have a psychiatric condition that, in the judgment of the study physician would make study participation unsafe or which would make treatment compliance difficult
3. be a significant suicidal/homicidal risk
4. have a medical condition that, in the judgment of the study physician, would make study participation unsafe or which would make treatment compliance difficult. Such conditions include, but are not limited to:

   * liver function tests greater than 3 times upper limit of normal
   * serum creatinine greater than 2 mg/dL
5. have had clinically significant cardiovascular or cerebrovascular disease within the past 6 months or have clinically significant ECG abnormalities
6. have taken an investigational drug within 30 days before consent
7. be taking concomitant medications that are contraindicated for use with the NNS or varenicline
8. be taking any concomitant medications that could increase the likelihood of smoking cessation (such as wellbutrin or nortriptyline)
9. have a known or suspected hypersensitivity to varenicline or the nicotine nasal spray (NNS)
10. use/have used smoking-cessation counseling programs with individual counseling or smoking-cessation medication treatments currently, or within 30 days before consent
11. have used electronic cigarettes or tobacco products, other than cigarettes, in the week before consent
12. be pregnant or breastfeeding
13. be anyone who, in the judgment of the investigator, would not be expected to complete the study protocol (e.g., due to relocation from the clinic area, probable incarceration, etc.)

Answer: C