Table 1.

List of the Clinical Trials from https://clinicaltrials.gov, Updated on 14-04-2023

	Title	Study Year	Conditions	Intervention	Outcome Measures	Number of Participants (n)
1	Smoking Cessation Self-Help for Dual Users of Tobacco Cigarettes and E-Cigarettes30	2021	Smoking cessation	Behavioral: GENERIC Behavioral: eTARGET	Rate of smoking abstinence Changes in the use of tobacco products	2896
2	Smoking Cessation and Reduction With an Electronic Nicotine Delivery Device (ENDD)31	2013	Nicotine dependence Smoking cessation	Device: E-cigarette 7.2 mg nicotine	Sustained 50% reduction in the number of cig/day at week 24 from baseline (reducers) Sustained 80% reduction in the number of cig/day at week 24 from baseline (heavy reducers)	40
3	Zonisamide/ Bupropion Effects on Switching to Electronic Cigarettes32	2022	Smoking cessation	Drug: Zonisamide Drug: Bupropion Other: Halo G6 e-cigarettes	Number of participants that completely switched from combustible cigarettes to Halo G6 e-cigarettes Point abstinence from combustible cigarettes Change in the rewarding effects of smoking combustible cigarettes	26
4	Enhanced E-cigarette Coaching Intervention for Dual Users of Cigarettes and E-cigarettes33	2022	Smoking cessation	Behavioral: Enhanced E-cigarette coaching Behavioral: Quitline treatment as usual	Treatment satisfaction and acceptability measured on a scale from 1–6 (very satisfied to very dissatisfied) Treatment engagement: call completion Quit plan development experience Knowledge and beliefs on E-cigarette	110
5	Combination of E-cigarettes and Varenicline for Tobacco Harm Reduction34	2022	Smoking cessation Harm reduction	Drug: Varenicline Other: E-cigarettes	Number of participants reporting continuous complete switching from cigarettes to Halo G6 Number of participants confirmed (by expired air CO) to have switched from cigarettes to Halo G6 Number of participants reporting point abstinence from smoking cigarettes at 6 months post-switch	25
6	The END Perioperative Smoking Pilot Study35	2022	Smoking Nicotine addiction Surgery	Behavioral ENDD Drug: NRT	Smoking status on the day of surgery (48-h point-prevalence abstinence), by self-report and confirmed with exhaled carbon monoxide (CO) Frequency of product use: number reporting use daily or most days Report of how helpful the product was for quitting How satisfied the patient was with the product (e-cigarette or patch) How likely the patient would be to recommend the product (e-cigarette or patch) to others Smoking status 8 weeks after randomization (confirmed by exhaled CO) Smoking reduction Number of participants with dual use	30
7	Behavioral and Enhanced Perinatal Intervention for Cessation (B-EPIC): Reducing Tobacco Use Among Opioid Addicted Women36	2020	Smoking cessation	Behavioral: Behavioral and enhanced perinatal intervention for cessation (B-EPIC) Behavioral	Change in the number of cigarettes smoked per day Change in urine cotinine concentration level Change in electronic cigarette usage per day Change in cigarette dependence Change in electronic cigarette dependence Change in maternal depression over time Change in maternal anxiety over time Change in maternal perceived stress over time	78