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Pharmacogenetic Dosing of Warfarin

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02065388
Enrollment
300
Registered
2014-02-19
Start date
2009-09-30
Completion date
2013-12-31
Last updated
2014-02-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Atrial Fibrillation, Atrial Flutter, Stroke, Venous Thrombosis

Brief 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.

Interventions

BEHAVIORALStandard of care dosing for warfarin
GENETICGenotype-guided dosingTaiwan algorithm for warfarin
GENETICGenotype-guided dosing IWPC algorithm for warfarin

Sponsors

Chang Gung Memorial Hospital
CollaboratorOTHER
China Medical University Hospital
CollaboratorOTHER
Kaohsiung Medical University
CollaboratorOTHER
Academia Sinica, Taiwan
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
20 Years to No maximum
Healthy volunteers
No

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

Design outcomes

Primary

MeasureTime frameDescription
Time spent in target INR rangefirst month of therapytime 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.

Countries

Taiwan

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 7, 2026