The Role of Nicotine and Non-Nicotine Alkaloids in E-Cigarette Use and Dependence

The study will shed light on the behavioral effects of: 1) varying e-cigarette nicotine
content, known to be important in maintaining conventional cigarette use; and 2) varying
e-cigarette non-nicotine tobacco alkaloid (NNTA) content, about which little is known
regarding the role in product use or dependence. The study will assess the effects of
e-cigarette nicotine and NNTA content on cigarette smokers who will be randomized to
conditions that manipulate the nicotine and NNTA content of e-cigarettes.

The study will include N = 375 adult smokers of menthol or non-menthol cigarettes with
randomization of enrolled participants to one of three groups (125/group).

Group 1: Nicotine + NNTAs. (Standard Nicotine Standard NNTA group) E-cigarette cartridges
will contain tobacco extract with nicotine + NNTA amounts in the range of typical commercial
cigarettes, with a ratio of NNTA:nicotine that is also typical of commercial cigarettes.

Group 2: Nicotine control (Standard Nicotine Low NNTA group). E-cigarette cartridges will
contain the same concentration of nicotine, but 1/10th of NNTAs as in Group 1. This group
will control for nicotine content and allow for evaluation of the roll of various levels of
NNTAs in e-cigarette use.

Group 3: Vehicle control (Low Nicotine, Low NNTA Group). E-cigarette cartridges will contain
less than 1/10 of the nicotine in the other two groups, and NNTA levels will be
correspondingly low. This group will control for changes in cigarette consumption that may
occur due to study participation or to the non-nicotine behavioral/sensory factors entailed
in e-cigarette use, which could influence cigarette consumption.

Inclusion Criteria:

- Have no known serious medical conditions;

- Are 18-65 years old;

- Smoke an average of at least 10 cigarettes per day;

- Have smoked at least one cumulative year;

- Have an expired air CO reading of at least 10ppm;

- Are able to read and understand English.

Potential subjects must agree to use acceptable contraception during their participation in
this study. Potential subjects must agree to avoid the following during their participation
in this study:

- Participation in any other nicotine-related modification strategy outside of this
protocol;

- Use of tobacco products other than cigarettes, including pipe tobacco, cigars, snuff,
and chewing tobacco;

- Use of e-cigarettes other than the ones provided during the study;

- Use of experimental (investigational) drugs or devices;

- Use of illegal drugs.

Exclusion Criteria:

- Intent to quit smoking with FDA approved pharmaceutical products within the next 90
days;

- Hypertension (systolic >160 mm Hg, diastolic >100 mm Hg. Participants with a history
of hypertension may, however, be allowed to participate in the study if the study
physician or physician assistant determines that the condition is stable, controlled
by medication, and in no way jeopardizes the individual's safety;

- Coronary heart disease;

- Lifetime history of heart attack;

- Clinically significant cardiac rhythm disorder (irregular heart rhythm);

- Chest pains (unless history, exam, and ECG clearly indicate a non-cardiac source);

- Clinically significant cardiac (heart) disorder (including but not limited to valvular
heart disease, heart murmur, heart failure);

- Clinically significant liver or kidney disorder (except kidney stones, gallstones);

- Clinically significant gastrointestinal problems or disease;

- Active ulcer in the past 30 days;

- Migraine headaches that occur more frequently than once per week;

- Clinically significant symptomatic lung disorder (including but not limited to chronic
obstructive pulmonary disease (COPD), emphysema, and asthma);

- Recent history of fainting;

- Problems giving blood samples;

- Diabetes;

- Current cancer or treatment for cancer in the past six months (except basal or
squamous cell skin cancer);

- Other major medical condition;

- Current psychiatric disease (with the exception of anxiety disorders, obsessive
compulsive disorder (OCD) and Attention Deficit Hyperactivity Disorder (ADHD));

- Current depression;

- Pregnant or nursing mothers;

- Chronic use of opiate medications for pain or sleep (non-opiate medication for pain or
sleep will be allowed);

- Use (within the past 30 days) of: Illegal drugs (or if the urine drug screen is
positive); Experimental (investigational) drugs; Psychiatric medications including
antidepressants, anti-psychotics or any other medications that are known to affect
smoking cessation (e.g. clonidine); Smokeless tobacco (chewing tobacco, snuff),
e-cigarettes, pipes, nicotine replacement therapy, or other smoking cessation
treatment; E-cigarettes;

- Smoking more than one cigar a month;

- Self-report of consuming 4 or more alcoholic drinks on 4 or more days per week;

- Current participation or recent participation (in the past 30 days) in another smoking
study at our Center or another research facility.