Puff Topography and Sensory Effects Across IQOS Device Generations

Puff Topography and Sensory Effects Across IQOS Device Generations: A Randomized Crossover Study

The goal of this clinical trial is to learn how people use two generations of IQOS heated tobacco devices and how each device affects their smoking behavior and sensory experience.

The main questions it aims to answer are:

• Do participants puff differently when using the newer IQOS Iluma i compared to the older IQOS 2.4?
• Does the flavor of the tobacco stick (preferred flavor vs. standard tobacco flavor) affect puffing behavior or sensory experience?
• What are the differences in throat hit, mouthfeel, and satisfaction between the two devices?

Participants will:

• Attend 2 laboratory visits at the American University of Beirut
• Use both the IQOS Iluma i and IQOS 2.4 devices during each visit
• Have their puffing behavior recorded automatically during device use
• Provide a breath sample before and after each use session
• Complete short questionnaires about how each device felt and their urge to smoke

Study Overview

• Status: Not yet recruiting
• Conditions: Tobacco Use; Nicotine Dependence
• Intervention / Treatment: Device: IQOS Iluma i with TEREA Tobacco Sticks; Device: IQOS 2.4 with HEETS Tobacco Sticks

Detailed Description

Heated tobacco products (HTPs) such as IQOS have evolved across generations, with newer models using induction-based heating rather than a ceramic blade. Nicotine yields have declined across generations, raising the possibility that sensory characteristics have been modified to maintain product appeal. Current emissions assessments rely on standardized machine-puffing regimens derived from cigarette testing, which may not reflect real-world IQOS user behavior. This study will characterize puff topography (volume, duration, flow rate, inter-puff interval, number of puffs) in 50 exclusive IQOS users during ad-libitum use of the IQOS Iluma i and IQOS 2.4 under preferred and standardized (Amber) flavor conditions. A randomized crossover design with two visits will be used, with device order within each visit randomized using a Williams design. Secondary outcomes include chemosensory ratings (mouthfeel, ease of draw, throat hit), and subjective effects (satisfaction, pleasantness, taste, urges). Data will inform device-specific puffing regimens for use in future emissions assessments.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Soha Talih, PhD; Phone Number: 3627 +961-1-350000; Email: st38@aub.edu.lb
• Study Contact Backup: Name: Mario El Hourani, PhD; Phone Number: +96170715263; Email: me217@aub.edu.lb

Study Locations

• Lebanon
  • Beirut, Lebanon
    • Clinical Aerosol Technology Laboratory (CATLAB), American University of Beirut

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Current IQOS user (at least 3 days per week in the past 30 days)
• Age 18 to 65 years
• Generally healthy
• Willing to provide informed written consent
• Willing to attend all laboratory visits
• Willing to abstain from all nicotine and tobacco products for at least 12 hours before each visit

Exclusion Criteria:

• Use of any tobacco products other than IQOS in the past 30 days
• Chronic cardiovascular conditions, seizures, or abnormal blood pressure
• Current psychiatric disorder requiring active treatment, including major depressive disorder
• Regular use of prescription medications that may influence cardiovascular function, respiratory function, or nicotine metabolism (excluding vitamins or birth control)
• Use of cocaine, opioids, benzodiazepines, or methamphetamines in the past month
• Marijuana use on more than 15 days per month
• Current pregnancy or breastfeeding
• Plans to quit nicotine or tobacco products within the next 30 days

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: IQOS Iluma i (Induction Heating); Participants use the IQOS Iluma i device with TEREA tobacco sticks under two flavor conditions (preferred flavor and standardized Amber flavor) across study visits. The IQOS Iluma i uses induction-based heating technology.	Device: IQOS Iluma i with TEREA Tobacco Sticks; The IQOS Iluma i is an induction-heated tobacco device used with TEREA STICKS. Participants use the device ad libitum during two smoking bouts (preferred flavor and Amber flavor conditions) across two study visits. Puff topography is recorded continuously during use.
Active Comparator: IQOS 2.4 (Blade Heating); Participants use the IQOS 2.4 device with HEETS tobacco sticks under two flavor conditions (preferred flavor and standardized Amber flavor) across study visits. The IQOS 2.4 uses ceramic blade heating technology.	Device: IQOS 2.4 with HEETS Tobacco Sticks; The IQOS 2.4 is a ceramic blade-heated tobacco device used with HEETS tobacco sticks. Participants use the device ad libitum during two smoking bouts (preferred flavor and Amber flavor conditions) across two study visits. Puff topography is recorded continuously during use.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Chemosensory Effects - Mouthful	Chemosensory Effects: Three sensory feedback items assessed after each smoking bout: (1) Mouthful - amount of aerosol filling the mouth, rated on a 1-5 visual analog scale (1 = barely any smoke to 5 = a lot of smoke); higher scores indicate greater mouthful sensation.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Chemosensory Effects - Ease of draw	Chemosensory Effects: Three sensory feedback items assessed after each smoking bout: (2) Ease of draw - effort required to draw a puff, rated on a 1-5 visual analog scale (1 = easy to 5 = hard); higher scores indicate greater effort required.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Chemosensory Effects - Throat hit	Chemosensory Effects: Three sensory feedback items assessed after each smoking bout: (3) Throat hit - intensity of throat sensation, rated on a 0-100 General Labeled Magnitude Scale (0 = barely detectable to 100 = strongest imaginable); higher scores indicate greater throat hit intensity.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Mean Puff Duration	Mean duration (seconds) of each puff recorded continuously during ad-libitum use of each device using the eTOP puff topography instrument.	Continuously during each ad-libitum smoking bout, at Visit 1 (day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Number of Puffs Per Stick	Total number of puffs taken per tobacco stick during each ad-libitum smoking bout, recorded using the eTOP puff topography instrument.	Continuously during each ad-libitum smoking bout, at Visit 1 (day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Mean Inter-Puff Interval	Mean time (seconds) between the end of one puff and the start of the next, recorded continuously during ad-libitum use of each device using the eTOP puff topography instrument.	Continuously during each ad-libitum smoking bout, at Visit 1 (day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Mean Puff Flow Rate	Mean peak puff flow rate (mL/s) recorded continuously during ad-libitum use of each device using the eTOP puff topography instrument.	Continuously during each ad-libitum smoking bout, at Visit 1 (day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Urge to Use IQOS - Factor 1: desire/intention	Urge to use IQOS assessed using a 10-item adaptation of the Questionnaire on Smoking Urges-Brief (QSU-Brief), rated on a 7-point scale (1 = Strongly Disagree to 7 = Strongly Agree). Higher scores indicate greater urge to use IQOS. Total score and subscale scores (Factor 1: desire/intention; Factor 2: negative reinforcement) will be reported.	Immediately before and immediately after each smoking bout, at Visit 1 (day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Urge to Use IQOS - Factor 2: negative reinforcement	Urge to use IQOS assessed using a 10-item adaptation of the Questionnaire on Smoking Urges-Brief (QSU-Brief), rated on a 7-point scale (1 = Strongly Disagree to 7 = Strongly Agree). Higher scores indicate greater urge to use IQOS. Total score and subscale scores (Factor 1: desire/intention; Factor 2: negative reinforcement) will be reported.	Immediately before and immediately after each smoking bout, at Visit 1 (day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - satisfaction	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - taste	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - throat/chest sensations	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - calm	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - awake	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - irritable	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - concentration	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - hungry	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - dizziness	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - nausea	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - craving relief	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)
Subjective Effects of IQOS Use - enjoyment	12-item questionnaire assessing subjective effects of IQOS use, rated on a 7-point scale (1 = Not at all to 7 = Extremely). Higher scores indicate greater intensity of the effect. Items assess: satisfaction, taste, throat/chest sensations, calming, alertness, irritability relief, concentration, hunger suppression, dizziness, nausea, craving relief, and enjoyment. Each item is reported individually. The questionnaire is a modified version of the Subjective Effects Questionnaire (SEQ), adapted for IQOS.	Immediately after each smoking bout, at Visit 1 (Day 1) and Visit 2 (Visit 2 scheduled at least 48 hours after Visit 1)

Collaborators and Investigators

• Sponsor: American University of Beirut Medical Center
• Investigators: Principal Investigator: Soha Talih, American University of Beirut Medical Center

Study record dates

Study Major Dates

• Study Start (Estimated): July 20, 2026
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): December 15, 2027

Study Registration Dates

• First Submitted: July 3, 2026
• First Submitted That Met QC Criteria: July 13, 2026
• First Posted (Actual): July 20, 2026

Study Record Updates

• Last Update Posted (Actual): July 20, 2026
• Last Update Submitted That Met QC Criteria: July 13, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Nicotine; Subjective Effects; IQOS; Heated Tobacco Products; Electronic Nicotine Delivery Systems; Tobacco Harm Reduction; Puff Topography
• Additional Relevant MeSH Terms: Mental Disorders; Substance-Related Disorders; Chemically-Induced Disorders; Behavior; Smoking; Tobacco Use Disorder; Vaping; Tobacco Use
• Other Study ID Numbers: BIO-2026-0012; AUB (Other Grant/Funding Number: American University of Beirut)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared. Data are stored on password-protected institutional computers at the American University of Beirut and are accessible only to authorized study personnel. Data may be made available to qualified researchers upon reasonable request to the corresponding author.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No