Please select the eligibility criteria that correspond to the clinical trial below.
Title: Effects of a Tailored Dose of Varenicline on Post-quitting Urges to Smoke
Brief Summary: Varenicline is a partial nicotinic agonist which acts on alpha4 beta2 nicotinic receptors. It is presumed to alleviate withdrawal discomfort, but also to diminish rewarding effects of cigarettes. The standard varenicline dosing has been formulated to avoid adverse reactions (primarily nausea) in sensitive clients. The downside of this cautious approach is that a substantial proportion of clients may be under-dosed. A blanket dose increase would inevitably increase the incidence of side effects, but it is likely that tailoring varenicline dosing to clients' needs would be safe and may further increase varenicline's efficacy.

This study will recruit 200 smokers who report little change to their enjoyment of cigarettes and no nausea, during the first week of varenicline use. These smokers will be randomised to receive the standard dose plus placebo or plus individualised varenicline dose up to 5mg, titrated over the next week prior to their target quit day. Urges to smoke, and other withdrawal symptoms, experienced during the study period will be compared between groups to see if the tailored therapy may be useful.


Options:
A: Inclusion Criteria:

* Subjects must have smoked an average of 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.

Exclusion Criteria:

* Subjects with clinically significant, recent cardiovascular disease.
B: Inclusion Criteria:

* Male or female cigarette smokers, 18-75 years, motivated to stop smoking and considered suitable for a smoking cessation attempt
* Smoked an average of at least 10 cigarettes per day during past year and over past month, and exhaled carbon monoxide (CO) \> 10 ppm at screening
* Current or past diagnosis of MDD without psychotic features, either single or recurrent, using DSM IV TR based on clinical assessment and confirmed by SCID and at least one of the following:
* On stable antidepressant treatment for MDD (stable dose for at least 2 months)
* Major depressive episode, using DSM IV TR, in the past 2 years successfully treated

Exclusion Criteria:

* Current or past diagnosis of dementia, schizophrenia, schizoaffective disorder, or other psychotic disorder, bipolar I disorder, bipolar II disorder.
* Subjects with antisocial, schizotypal, or any other personality disorder severe enough to compromise the subject's ability to comply with the study requirements..
* Current use of either bupropion or nortryptiline.
C: Inclusion Criteria:

* Smoker seeking treatment
* Aged 18 and over
* Consenting to take part
* Report little or no change in enjoyment of cigarettes and/or nausea

Exclusion Criteria:

* Pregnant or breastfeeding
* Have severe kidney disease
* Have severe heart problems
* Have a current psychiatric illness
* Are unable to fill in questionnaires in English
* Have an allergy to varenicline
* Are currently involved in another clinical trial
D: Inclusion Criteria:

* Males and females between 18 and 55 years old will be eligible for this study. Females must not be pregnant as determined by pregnancy screening, nor breast feeding, and must be using acceptable birth control methods during study participation.
* Current opioid dependence as evidenced by documentation of prior treatment for opioid dependence or signs of withdrawal, self-reported history of opioid dependence for consecutive 12 month period and a positive urine for opiates.
* Subjects must fulfill Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for opioid dependence.
* Subjects must have a history of cocaine use, with a reported street cocaine use of a minimum of 1/2 gram during the preceding 30 days.
* Subjects must meet DSM-IV criteria for cocaine dependence or abuse, and have laboratory confirmation of recent cocaine use (positive urine for cocaine) during the month prior to study entry.
* Subjects must be treatment-seekers for opioid and cocaine use.
* Subjects must have smoked at least 10 cigarette per day for at least one year. Varenicline's safety has only been studied in smokers.

Exclusion Criteria:

* History of heart disease, left ventricular hypertrophy, ischemic ECG changes, chest pain, arrhythmia, hypertension.
* History of severe renal or hepatic diseases.
* History of psychosis, schizophrenia, bipolar or major depressive disorder.
* History of seizure disorder.
* Current diagnosis of alcohol, benzodiazepine and other drug abuse or dependence (other than opiates, cocaine, and nicotine).
* Current use of over-the-counter or prescription psychoactive drugs (antidepressant, anxiolytics, antipsychotics, mood stabilizers, psychostimulants).
* Liver function tests (ALT or AST) greater than 3 times normal.
* Known allergy to varenicline or methadone.

Answer: C