Gender Differences in Switching From Smoking Regular Cigarettes to E-Cigarettes

PRIMARY OBJECTIVES:

I. To characterize the effects of switching to nicotine vs. placebo standard research
E-cigarettes (SRECs) from combustible cigarettes (CCs) on product use, product acceptability,
reinforcement, and nicotine dependence symptoms among adult daily CC smokers.

II. To characterize the differences between male and female CC smokers when switching to
nicotine versus (vs.) placebo SRECs from CCs on product use, product acceptability,
reinforcement, and nicotine dependence symptoms.

EXPLORATORY OBJECTIVES:

I. To characterize which factors moderate or mediate the effects of switching to nicotine and
placebo SRECs from CCs among male and female CC smokers.

OUTLINE:

Participants will be instructed to smoke their usual brand cigarette as they normally would
in weeks 1-2 (Phase I) and to use only the SREC (with or without nicotine) in weeks 3-4
(Phase II) and in weeks 5-6 (Phase III). Participant assignment to SREC type at Phases II and
III will be counter-balanced within group, with half of men and women receiving the placebo
SREC during Phase II and half during Phase III. Participants will attend 4 laboratory visits
with study investigators for 3 hours each over 6 weeks of study participation.

Inclusion Criteria:

- Current smoker, defined as smoking 5 or more cigarettes per day during the past 30
days.

- Produce an expired carbon monoxide (CO) of 5 parts per million (ppm) or more.

- A stable address and working telephone.

- Able to follow verbal and written instructions in English and complete all aspects of
the study as determined by principal investigator (PI).

- Interested in trying electronic cigarettes (ECs).

Exclusion Criteria:

- Use of electronic cigarettes on more than 2 days in the past 30 days.

- Meet criteria for current major depressive disorder or suicidality.

- Report more than once weekly use of tobacco products other than cigarettes during the
past 30 days.

- Report recent (past 30 days) or planned (within the next 45 days) involvement in
smoking cessation activities.

- Uncontrolled or unstable medical condition (e.g., uncontrolled hypertension, angina,
diabetes).

- Evidence of cognitive deficits or instability that would preclude reliable study
participation.

- Women who are pregnant, breastfeeding, or are not using an acceptable method of birth
control (if capable of becoming pregnant).

- Considered by the investigator to be an unsuitable or unstable candidate (including
but not limited to the following situations: planned absences from Houston area, or
unwilling or unable to comply with study procedures).