Homogeneous interferon from E. coli depresses hepatic cytochrome P-450 and drug biotransformation

A highly purified homogeneous human interferon produced from cloned genes depressed the levels of hepatic cytochrome P-450 and related xenobiotic metabolism. Using another cloned human interferon and several impure preparations of human and mouse interferon, it appears that only interferons with antiviral activity in the mouse depress cytochrome P-450 in that species. This is the first direct evidence that interferon decreases hepatic drug biotransformation and likely explains the depression of drug elimination which occurs during viral infections or following the administration of interferon inducers.