Pharmacogenetic Dosing of Warfarin

Stroke Clinical Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02065388
• Other study ID #: AS-IRB01-100070
• Status: Completed
• Phase: Phase 3
• First received: February 9, 2014
• Last updated: February 16, 2014
• Start date: September 2009
• Est. completion date: December 2013

Study information

• Verified date: February 2014
• Source: Academia Sinica, Taiwan
• Contact: n/a
• Is FDA regulated: No
• Health authority: Taiwan: Ministry of Health and Welfare
• Study type: Interventional

Clinical Trial Summary

Purpose:

Warfarin is now the most commonly used oral anticoagulant. This drug has inter-individual variability due to the genetic polymorphisms in the warfarin metabolizing enzyme, CYP2C9 and warfarin target, VKORC1. The investigators' team developed a pharmacogenetic dosing algorithm which can predict patients required warfarin dose, thus could prevent warfarin induced warfarin adverse events.

Methods:

The investigators recruited patients with indications for warfarin, the genotypes of VKORC1 and CYP2C9 were determined by the hospitals and verified by National Center for Genome Medicine. The investigators then randomized the patients to one of three arms: 1. Warfarin dose predicted by dosing algorithm developed by the International Warfarin pharmacogenetic Consortium (IWPC), 2. Algorithm developed by the Taiwan Warfarin Consortium and 3. Standard of care. The investigators aimed to determine whether using genetic dosing algorithm can lead to more stable dose and safer use of the drug.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 300
• Est. completion date: December 2013
• Est. primary completion date: December 2013
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 20 Years and older

Eligibility

Inclusion Criteria:

• Patients must give their informed consent and complete the case report form.

• Patients must be over the age of 20.

• Patients have clinical indications for warfarin therapy but do not have any prior warfarin treatment.

Exclusion Criteria:

• Patients who did not complete the informed consent form or the CRF

• Patients who are less than the age of 20.

• Patients who had prior or is currently on warfarin treatment.

• Patients who have hemorrhagic tendencies or hemorrhagic diseases defined as copious bleeding caused by viral or bacterial infections; cancer and hepatic dysfunction defined as GOP and GPT values three times higher than normal value

• Patients who has Vitamin K deficiency

• Female patients who is currently pregnant

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Atrial Fibrillation
• Atrial Flutter
• Stroke
• Venous Thrombosis

Intervention

Behavioral:
• Standard of care dosing for warfarin

Genetic:
• Genotype-guided dosingTaiwan algorithm for warfarin

• Genotype-guided dosing IWPC algorithm for warfarin

Locations

Country	Name	City	State
Taiwan	Kaohsiung Medical University	Kaohsiung
Taiwan	China Medical University Hospital	Taichung
Taiwan	Chang Gung Memorial Hospital	Taoyuan

Sponsors (4)

Lead Sponsor	Collaborator
Academia Sinica, Taiwan	Chang Gung Memorial Hospital, China Medical University Hospital, Kaohsiung Medical University

Country where clinical trial is conducted

Taiwan, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Time spent in target INR range	time spent in target INR range Time in the target INR Range will be the primary endpoints because of its strong association with adverse events: patients with subtherapeutic INR values are at increased risk of thrombosis and patients with high INR values are at increased risk of hemorrhage during warfarin treatment initiation.	first month of therapy	Yes