Table 1.

Kinetic parameters for simvastatin hydroxy acid (SVA) metabolite formation by human liver microsomes and human recombinant CYPs.

	M1			M2			M3
	Km µM	Vmax nmol min−1 mg−1or nmol min−1 pmol−1 P450	CLint mL min−1 mg−1 or mL min−1pmol−1 P450	Km µM	Vmax nmol min−1 mg−1 or nmol min−1 pmol−1 P450	CLint mL min−1 mg−1 or mL min−1pmol−1 P450	Km µM	Vmax nmol min−1 mg−1 or nmol min−1 pmol−1 P450	CLint mL min−1 mg−1 or mL min−1pmol−1 P450
Human livermicrosomes	76±35*	1.9±1.8	0.020±0.01	47±12	0.86±0.26	0.020±0.01	47±21	0.59±0.16	0.015±0.01
CYP3A4	26	7.3 (2.6)†	0.28	29	4.6 (2.1)	0.16	21	2.8 (1.3)	0.13
CYP2C8	88	2.8 (0.27)	0.032	36	0.85 (0.17)	0.024	16	0.60 (0.19)	0.038
CYP3A5		(0.70)			(0.56)			(0.26)
CYP2D6		(ND)‡			(ND)			(ND)
CYP2C9		(ND)			(ND)			(ND)
CYP2C19		(ND)			(ND)			(ND)
CYP1A2		(ND)			(ND)			(ND)
CYP2A6		(ND)			(ND)			(ND)

^*Values are mean ± SD obtained form six individual subjects. V_max and CLint values are expressed per mg microsomal protein.

^†Values in parentheses were obtained using 100 µm SVA. V_max and CLint values are expressed per pmol P450.

^‡ND, Not detectable (< 0.005 nmol min⁻¹ pmol⁻¹ P450).