Table 1.

Binding rates and affinity of ritonavir to CYP3A4

		CYP3A4
	ferric	ferrous	ferric, BEC-bound
Ks*, nM	51 ± 10	45 ± 13	50 ± 5
Kd†, μM	0.84 ± 0.05	0.94 ± 0.16	1.24 ± 0.15
kfast‡, s-1	1.42 ± 0.3	1.43 ± 0.3	1.42 ± 0.2
kslow§, s-1	0.23 ± 0.04	0.20 ± 0.02	0.24 ± 0.04

^*Spectroscopic dissociation constant for the CYP3A4-ritonavir complex.

^†Kinetic dissociation constant for the CYP3A4-ritonavir complex.

^‡Rate constant for the fast phase of the CYP3A4-ritonavir binding reaction.

^§Rate constant for the slow phase of the CYP3A4-ritonavir binding reaction.