This study investigates the feasibility, acceptability, and short-term effects of providing 4 weeks of complimentary electronic cigarettes (ECs) to 30 individuals who did not quit after smoking cessation treatment provided in the context of lung cancer screening and do not plan to quit smoking. This open-label single-arm pilot clinical trial will test the impact of EC provision on: 1) study feasibility, 2) EC acceptability, 3) tobacco use behavior (e.g., cigarettes per day, EC use), and 4) biomarkers (e.g., carbon monoxide, cotinine, and anabasine). Participants will be asked to switch from combustible cigarettes to the NJOY ACE 5% nicotine electronic cigarette (EC) for 4 weeks. They will be followed an additional 4 weeks after EC provision ends (to 8 weeks).

The first study hypothesis is that more than 40% of eligible smokers who are offered participation in the trial will enroll, and that 75% of enrollees will complete the trial. The second study hypothesis is that participants will report fewer cigarettes smoked per day at the end of 4 weeks of EC provision, relative to their baseline values.

Inclusion Criteria:

• Participants who completed the Screen Assist study (NCT03611881) and self-reported smoking cigarettes at the end of the study were asked to complete a survey to ascertain their potential interest in participating in a research study to test the effects of switching from combustible cigarettes (CC) to electronic cigarettes (EC). Individuals who expressed interest in switching to EC on that survey were screened for eligibility for this pilot study
• Smoked ≥5 cigarettes/day in past month
• Smoking status at study entry confirmed by breath carbon monoxide (CO) ≥ 6ppm
• Willing to try switching from CC to EC for 4 weeks
• Owns a mobile telephone
• English speaking
• Willing to travel to the Massachusetts General Hospital campus for 3 in-person visits.

Exclusion Criteria:

• Plans to quit smoking and has set a quit date in the next 30 days
• Used smoking cessation treatment in the past 30 days
• Used EC on >2 days in the past 30 days
• Hospitalized for acute coronary syndrome, unstable angina, congestive heart failure, stroke, pneumonia or chronic pulmonary disease/asthma exacerbation in the past 1 month
• Not willing to abstain from smoking marijuana in the 24h before each study visit

Adverse event data were collected for 8 weeks

Adverse event collection occurred at the end of every study visit using a form where participants were asked about serious adverse events since the previous visit.