The Relationship between Genetic Variations of CYP2A6 and Pharmacokinetics of Nicotine and Hair Nicotine Metabolites in Cigarette Smokers Visiting Medical Check-Up Clinic at King Chulalongkorn Memorial Hospital

Not Applicable

• Conditions: The requires a hair samples to determine the concentrations of nicotine and cotinine. Therefore, it is possible that some smokers do not consent to collect hair samples.; Nicotine; Cotinine; trans- 3’- hydroxycotinine; CYP2A6

• Registration Number: TCTR20161227002
• Lead Sponsor: the 90th Anniversary of Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund)

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Study Start: 2016-12-27
• Study Completion: 2017-03-01
• Last Update Posted: 19 August 2024

Recruitment & Eligibility

• Status: Enrolling by invitation
• Sex: All
• Target Recruitment: 18

Inclusion Criteria

Study I : Genotyping of CYP2A6
1. Thai smokers visiting medical check-up clinic at King Chulalongkorn Memorial Hospital
2. Age of smoker between 18-60 years
3. Current smoker and defined as smoking >100 cigarette at least 5 months determined by Fagerström Test for Nicotine Dependence (FTND) test
4. Written informed consent

Study II : Pharmacokinetics of nicotine
1. Thai smoker had normal metabolizers (CYP2A6*1A/*1A, CYP2A6*1A/*1B, and CYP2A6*1B/*1B) or slow metabolizers (CYP2A6*1A/*4, CYP2A6*1A/*9, CYP2A6*1B/*9, CYP2A6*9/*9, CYP2A6*4/*4, CYP2A6*4/*9 and CYP2A6*1B/*4)
2. Abstain from smoking (tobacco and nicotine replacement therapy) for 12 hours prior to the study
3. Agree to keep the hair root from the back of scalp length of 5 centimeters and 100 milligram of hairs
4. Written informed consent

Exclusion Criteria

Study I : Genotyping of CYP2A6
1. Who had use medication within 14 days prior to the start of the study
2. Liver and kidney disease
3. During pregnancy or breast feeding
4. Participation in another clinical trial within 30 days

Study II : Pharmacokinetics of nicotine
1. Who had use medication within 14 days prior to the start of the study
2. Liver and kidney disease
3. During pregnancy or breast feeding
4. Who had a history of temporomandibular joint disease or pain
5. Participation in another clinical trial within 30 days

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
CYP2A6 genetic variation (Normal metabolizers and Slow metabolizers) at 6 months Restriction fragment length polymorphism method (PCR-RFLP) and Real-time PCR

Secondary Outcome Measures

Name	Time	Method
Pharmacokinetics of nicotine and hair nicotine metabolites at 7 months Liquid chromatography tandem-mass spectrometry (LC-MS/MS) technique