Azamulin is a selective, irreversible inhibitor of cytochrome P450 (CYP) 3A isoforms (IC50 values range from 26 to 240 nM for CYP3A4 and CYP3A4/5 from different sources). [1] It is at least 50-fold less potent against CYP2J2 and 100-fold less effective against all other CYP isoforms. [1] Azamulin potently blocks the hydroxylation of testosterone and midazolam by CYP3A4.[2]
Reference:
[1]. Stresser, D.M., Broudy, M.I., Ho, T., et al. Highly selective inhibition of human CYP3Aa in vitro by azamulin and evidence that inhibition is irreversible. Drug Metabolism and Disposition 32(1), 105-112 (2004).
[2]. Lim, H.K., Duczak, N., Jr., Brougham, K., et al. Automated screening with confirmation of mechanism-based inactivation of CYP3A4, CYP2C9, CYP2C19, CYP2D6, and CYP1A2 in pooled human liver microsomes. Drug Metabolism and Disposition 33(8), 1211-1219 (2005).