Could taking chantix for a month before quitting boost success rates?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Smoking at least 10 cigarettes per day (CPD) for the past 6 months and expired-air carbon monoxide (CO) \>7 at intake. NOTE: To reduce exclusion of Black participants, the CPD criterion was reduced to 5 and the carbon monoxide criterion was eliminated in November, 2019. * At least moderately motivated to quit smoking and intention to make a quit attempt with varenicline 1 month after treatment begins. * Planning to remain in western New York (NY) during the study period * Willing to use varenicline and to refrain from other cessation treatments and tobacco products during the study period. * English speaker * To be intent-to-treat (ITT), the participant must complete Lab Visit 1 and meet minimal completion rate for real-world (EMA) assessments. Exclusion Criteria: * Use of other tobacco products, including e-cigarettes, in past 7 days * Use of smoking cessation medication, including nicotine replacement therapy, in the past 14 days * Prior allergy/hypersensitivity to varenicline * Pregnant or breast-feeding * Substance use: * Alcohol: AUDIT score \> 15 at intake, suggestive of alcohol dependence and warranting treatment; for those with scores between 8 and 15, the investigators will advise reducing drinking). * Medical treatment for substance use (SU) in past 3 months, including Suboxone (buprenorphine) and methadone (at phone screen) * Using a combination of the National Institute on Drug Abuse (NIDA) modified ASSIST (4-26 = moderate risk; 27+ = high risk) and urine toxicology screen (both at intake): * Cannabis: ASSIST=27+ (tox screen not used) * Cocaine: ASSIST=7+ OR positive tox screen * Methamphetamine: ASSIST=7+ OR positive tox screen * Inhalants, hallucinogens, sedatives, or sleeping pills: ASSIST score = 7+ * Prescription stimulants: With prescription, ASSIST 27+; Without prescription, ASSIST 7+ * Opioids: With prescription, ASSIST 27+ (note ineligible if prescription is for buprenorphine or methadone); Without prescription, ASSIST 7+ OR positive tox screen (Note: ASSIST 4+ modified to 7+ in 2018 to avoid excluding people with past SU problems. clinicaltrials.gov edited 12/18/18) * Psychiatric: * Antipsychotic medications * Lifetime history of schizophrenia or bipolar disorder * Evidence of current major depression (per Patient Health Questionnaire (PHQ-9) at intake * Past 10 years suicidal ideation (SI) / behavior. At intake, all of the following are exclusionary on the baseline Columbia-Suicide Severity Rating Scale (Posner et al., 2008): SI without intent (C-SSRS #1, #2, or #3), if any intensity rating (Frequency, Duration, Controllability, Deterrents, or Reasons for Ideation) is \> 2; SI with intent (C-SSRS #4, or #5), regardless of intensity ratings; Suicidal Behavior (any suicide attempt, interrupted attempt, aborted attempt, or suicide preparatory acts or behavior on the C-SSRS). * Any medical condition, illness, disorder or concomitant medication that compromises participant safety or treatment, as determined by the Principal Investigator and/or Study Physician. * Inability to provide informed consent or complete any of the study tasks as determined by the Principal Investigator and/or Study Physician.