Assessment of HPHC Exposure in Smokers Switching to THS/TP18 With Different Device Variants

Inclusion Criteria: * Participant has signed the ICF and understands the information provided in it. * Participant is male or female and between 21 and 65 years old (inclusive). * Participant has been a smoker for at least 2 years prior to the screening visit and is willing to switch to THS and TP18. * Participant has smoked on average ≥10 commercially available CIGs/day over the last 30 days. Smoking status will be verified based on a urinary cotinine test (cotinine ≥200 ng/mL). * Participant does not plan to quit smoking within the next three months. * Participant is available for the entire study period and willing to comply with the study procedures, including product use assignments and periods of abstinence from any nicotine/tobacco-containing products, and willing to adhere to a standardized diet (during confinement period and during overnight stays on Day 30 and Day 60). Exclusion Criteria: * As per the Investigator's judgment, the participant cannot participate in the study for any reason other than medical (e.g., psychological, social reason). * Participant is legally incompetent, or physically or mentally incapable of giving consent (e.g., in emergency situations, under guardianship, prisoners). * Participant has a health condition which requires medication or any other clinically relevant finding based on available assessments from the Screening period (e.g., safety panel, pulmonary function test, vital signs, physical examination, ECG, and medical history), as…