- ERMBT before and 20–26 h after IFN-α-2b injection, - IFN-α-2b induced a small significant decrease in ERMBT (p < 0.05), - at baseline CYP3A4 activity was lower in patients with hepatitis C but the effect of IFN appeared to be not different. The gene discussed is CYP3A4; the disease is hepatitis C virus infection.