The Effect of Electronic Cigarette Liquid Characteristics in Smokers.

Study Overview
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Brief Summary
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The purpose of this study is to determine differences in nicotine delivery, user behaviors, subjective effects, and physiological effects, when cigarette smokers use an electronic cigarette with different nicotine (and sweetener) concentrations relative to using their own brand of cigarettes.

Official Title
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The Effect of Electronic Cigarette Liquid Characteristics in Smokers.

Conditions
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Electronic Cigarettes

Intervention / Treatment
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* Other: Own Brand Cigarette
* Other: ECIG 15 mg nicotine, sweetened
* Other: ECIG 15 mg nicotine, unsweet
* Other: ECIG 0 mg nicotine, sweetened
* Other: ECIG 0 mg nicotine, unsweet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria-- Participants must be: Healthy (determined by self-report) Between the ages of 21-55 years old Current cigarette smokers Wiling to provide informed consent Able to attend the lab session and abstain from tobacco/nicotine products as required Agree to use designated products according to the study protocol Exclusion Criteria: Women if they are breast-feeding or test positive for pregnancy (by urinalysis) at screening. Individuals who weigh less than 110 pounds. Some study details about the eligibility criteria are purposely omitted at this time to preserve scientific integrity. Full details will be posted at the conclusion of the study.

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cigarette smokers<br>Each participant will participate in 5 sessions. During each session, participants will complete a 10-puff, directed product use bout, and then have the option later to puff as little or as much as they like during a 30-minute self administration task. Session 1: Own brand cigarette use Session 2: ECIG 15 mg nicotine, sweetened Session 3: ECIG Lab Session ECIG 15 mg nicotine, unsweetened Session 4: ECIG Lab Session ECIG 0 mg nicotine, sweetened Session 5: ECIG Lab Session ECIG 0 mg nicotine, unsweetened | Other: Own Brand Cigarette<br>* Effects of own brand cigarette use.<br>Other: ECIG 15 mg nicotine, sweetened<br>* Effects of using a 30 Watt ECIG filled with 15 mg nicotine, sweetened liquid<br>Other: ECIG 15 mg nicotine, unsweet<br>* Effects of using a 30 Watt ECIG filled with 15 mg nicotine, unsweet liquid<br>Other: ECIG 0 mg nicotine, sweetened<br>* Effects of using a 30 Watt ECIG filled with 0 mg nicotine, sweetened liquid<br>Other: ECIG 0 mg nicotine, unsweet<br>* Effects of using a 30 Watt ECIG filled with 0 mg nicotine, unsweet liquid<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma Nicotine Concentration | Change in plasma nicotine concentration. Changes in plasm nicotine concentration during puff bout are considered to be the more relevant and accurate values so analysis and results reporting will focus on change from baseline to immediately following 10-puff bout. | Blood will be taken 4 times in each session to examine changes from baseline (approx 70 minutes) to immediately following a ten-puff bout (approx 80 minutes), and immediately before (approx 140 minutes) and after the PRT (approx 180 minutes). | 
| Progressive Ratio Task - Breakpoint | The progressive ratio task (PRT) is a self-administration task that will take 30-minutes to complete. It will begin by requiring ten computer key presses to earn the first puff of the session product, and this requirement will increase by 30% (i.e., 10, 13, 17, etc.) after each reinforcer (puff) is earned and consumed. The PRT will have three outcome measures (1) breakpoint (maximum number of key presses completed to earn a puff), (2) number of puffs, and (3) latency (sec) to initiate key pressing. Breakpoint is reported here. | This task will begin approximately an hour and ten minutes after the 10-puff directed product use bout. | 
| Progressive Ratio Task - Number of Puffs | The progressive ratio task (PRT) is a self-administration task that will take 30-minutes to complete. It will begin by requiring ten computer key presses to earn the first puff of the session product, and this requirement will increase by 30% (i.e., 10, 13, 17, etc.) after each reinforcer (puff) is earned and consumed. The PRT will have three outcome measures (1) breakpoint (maximum number of key presses completed to earn a puff), (2) number of puffs, and (3) latency (sec) to initiate key pressing. Number of puffs is reported here. | This task will begin approximately an hour and ten minutes after the 10-puff directed product use bout. | 
| Progressive Ratio Task - Latency | The progressive ratio task (PRT) is a self-administration task that will take 30-minutes to complete. It will begin by requiring ten computer key presses to earn the first puff of the session product, and this requirement will increase by 30% (i.e., 10, 13, 17, etc.) after each reinforcer (puff) is earned and consumed. The PRT will have three outcome measures (1) breakpoint (maximum number of key presses completed to earn a puff), (2) number of puffs, and (3) latency (milliseconds) to initiate key pressing. Latency is reported here. | This task will begin approximately an hour and ten minutes after the 10-puff directed product use bout. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Puff Volume | The volume of each puff, in ml, averaged over the 10-puff use bout | Puff volume will be measured during the approximately 5-minute, 10-puff use bout. | 
| Puff Duration | The duration of each puff, in seconds, averaged over the 10-puff use bout | The duration of each puff will be measured during the approximately 5-minute, 10-puff use bout. |