Pharmacogenomics of Warfarin in Hispanics and Latinos

Thrombosis Clinical Trial

Official title:

Pharmacogenomics of Warfarin in Hispanics and Latinos

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT02972385
• Other study ID #: 1608762767
• Status: Recruiting
• Start date: September 2016
• Est. completion date: September 2022

Study information

• Verified date: April 2021
• Source: University of Arizona
• Contact: Jason H Karnes, PharmD, PhD
• Phone: 520-626-1447
• Email: karnes[@]pharmacy.arizona.edu
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Warfarin is a commonly used blood thinner to treat and prevent blood clots. It is important to take the right dose of warfarin because too much can increase the risk of bleeding and too little can increase the risk of blood clots. This is why patients are closely monitored especially when they begin warfarin therapy. When clinicians prescribe warfarin, they have to consider different factors such as patient's age, body size, diet, and other medications that can interact with warfarin.

Certain genes have also been found to affect warfarin dose. Individuals have variations in these genes, which can help explain why some patients need higher dose and others require less. These factors have been used to better predict a patient's warfarin dose requirement. However, these predictions were created based on Caucasian populations and they may not be accurate in predicting a safe warfarin dose if a patient is not Caucasian. This study aims to identify new genetic variation that affects warfarin dosing in Hispanic and Latino populations and try to better predict a Hispanic or Latino patient's warfarin dose requirement.

Description:

If the patient is willing to hear about the study, during routine clinical care, one of the patient's providers will approach patients meeting the study criteria about participation in the study. Study personnel will not approach potential participants unless permission is given to the patient's provider. If the patient would like to participate in the study, study personnel will discuss details of the study in person during the patient's routine clinical care visit. There will also be a flyers available for posting and for distribution to potential participants.

Participants consenting to the study will be asked to provide a cheek swab or mouthwash sample to provide buccal cells for DNA extraction. If the patient is receiving a blood draw during their regular clinical appointment, participants will be asked for a blood sample of 15 milliliters. Genomic DNA will be isolated for genotyping and patient plasma samples will also be stored.

Linear regression will be used to test association of SNPs with therapeutic warfarin dose using the algorithms derived by the International Warfarin Pharmacogenomics Consortium. The primary phenotype (weekly stable warfarin dose) will be transformed by square root. SNPs and other variables associated with warfarin dose will be assessed in univariate analyses and entered into stepwise linear regression to determine the adjusted association with dose requirements using R2. Quality control procedures will include deviation from Hardy-Weinberg Equilibrium, and SNP and sample exclusions based on call rates. Ancestry-informative marker (AIM) analysis will be performed to estimate ancestry in each individual.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 400
• Est. completion date: September 2022
• Est. primary completion date: September 2021
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• At least 18 years of age

• Ability to give informed consent

• Therapeutic INR for at least 2 consecutive clinic visits

• Self-identifies as Hispanic or Latino

Exclusion Criteria:

• Less than 18 years old

• Unable to give informed consent

• Severe hepatic impairment

Related Conditions & MeSH terms

• Hemorrhage
• Thrombosis

Intervention

Procedure:
• Mouthwash sample
A one time mouthwash sample will be performed.
• Blood Draw
Patients who are receiving a blood draw during their regular clinical appointment will be asked for a blood sample of 15 milliliters. Genomic DNA will be isolated for genotyping and patient plasma samples will also be stored.

Locations

Country	Name	City	State
United States	Banner University Medical Center - Tucson	Tucson	Arizona

Sponsors (1)

Lead Sponsor	Collaborator
University of Arizona

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Stable warfarin dose	Dose of warfarin required to maintain stable INR for at least 2 consecutive clinic visits.	At time of enrollment