Very Low Nicotine Content Cigarettes and E-Cigarettes in Promoting Smoking Cessation in Daily and Intermittent Cigarette Smokers

Unwilling to refrain from other e-cigarette use for the duration of the study, other than what is provided to them for study purposes

Current/recent use of certain medications:

* Smoking cessation meds (past 90 days; e.g., wellbutrin, bupropion, Zyban, nicotine replacement therapy \[NRT\], Chantix)

* Certain medications to treat depression (last 14 days; e.g., amitriptyline)

* A case by case determination will be made by study physician for medication on the precautionary list, (e.g. nitroglycerin)

* Self-reported daily use of opioids for 30 days or more on phone screen or at screening is exclusionary however pro re nata (PRN) use is allowed (e.g., 3 to 7 days per week or less or if more frequent, use less than a month's duration

Unstable medical condition as determined by the medical team

Self-reported bronchial or respiratory infection in the last 14 days (this criterion waived during COVID-19 pandemic)

Subject's spirometry forced expiratory volume in 1 second (FEV1) percentage reading is \< 50 (severe to very severe obstruction) (this criterion waived during COVID-19 pandemic)

Self-reported abnormal heart rhythms or cardiovascular disease (stroke, chest pain, heart attack) in the last 3 months

Meet criteria for major depressive syndrome or suicidality on the Patient Health Questionnaire-9 (PHQ-9)

Self report of past or current diagnosis of bi-polar disorder or schizophrenia/schizoaffective disorder

Self-reported other tobacco use besides cigarettes or little cigars (e.g., hookah, cigarillos, smokeless tobacco, chewing tobacco, pipes, cigars, etc.) on 10 or more days in the last month

Recent (past 90 days), current, or planned (within the next 45 days) involvement in smoking cessation activities

Positive urine pregnancy test at screening. Women who are two years post-menopausal, or who have had a tubal ligation or a partial or full hysterectomy will not be subject to a urine pregnancy test

Women that are breastfeeding or of childbearing potential and not protected by a medically acceptable, effective method of birth control while enrolled in the study. Medically acceptable contraceptives include:

* Approved hormonal contraceptives (such as birth control pills, patches, implants or injections)

* Barrier methods (such as condom or diaphragm) used with a spermicide, or

* An intrauterine device (IUD)

* Contraceptives sold for emergency use after unprotected sex are not acceptable methods for routine use

Subject considered by the investigator to be unsuitable to participate in the study (e.g., due to cognitive deficits or instability to last the entire duration of the study)

What this study is about