Furafylline is a potent and selective inhibitor of human cytochrome P450IA2 with an IC50 of 0.07 μM in kinase experiment. Furafylline is a methylxanthine derivative that is introduced as a long-acting replacement for theophylline in the treatment of asthma. Administration of Furafylline is associated with an elevation in plasma levels of caffeine, due to inhibition of caffeine oxidation, a reaction catalysed by one or more hydrocarbon-inducible isoenzymes of P450. Furafylline has either very little or no effect on human monooxygenase activities catalysed by other isoenzymes of P450, including P4501ID1, P4501IC, P450IIIA[1].
