Genetic Variability in the Response to Warfarin at Baseline and During Induction of CYP2C9

The genetic factors associated with variability in CYP2C9 induction have not been elucidated. The hypothesis underlying this study is that following 7 days treatment with rifampicin, a known CYP450 inducer, the genetic variability in regulatory elements controlling CYP2C9 expression will be associated with the magnitude of change in INR response to warfarin and in CYP2C9-mediated warfarin metabolism.

Inclusion Criteria:

• Healthy subjects

Exclusion Criteria:

• Consumption of any medication during 30 days
• Smoking
• Alcohol consumption