Cytochrome P450 3A Inducers

CYP3A4 and CYP3A5 are the cytochrome P450 monooxygenases of the CYP3A subfamily that this class is named for: CYP3A4 metabolises sterols, steroid hormones, retinoids and fatty acids, CYP3A5 steroid hormones and vitamins, both inserting one atom of molecular oxygen into the substrate and reducing the second to water with two electrons supplied by NADPH through cytochrome P450 reductase. Drugs in this class induce that activity - UniProt records CYP3A4 as induced by drugs such as rifampicin and CYP3A5 by glucocorticoids such as dexamethasone - so a co-administered substrate of the pathway is cleared faster and its exposure falls. FDA grades that consequence and defines an inducer by it: strong and moderate index inducers decrease the AUC of sensitive substrates of a given metabolic pathway by at least 80 percent and by 50 to under 80 percent respectively. A drug belongs here because its recorded effect on CYP3A is induction, not inhibition; as MED-RT populates the class its members are brigatinib, eslicarbazepine, lorlatinib, nevirapine, oritavancin and osimertinib.