TABLE 4

Kinetic parameters for 8-hydroxyefavirenz formation from S-efavirenz

Results (Vmax, K, n, Ki, and Vi) are the parameter estimates and S.E. of the estimate, determined by nonlinear regression analysis using a model of cooperative substrate binding with substrate inhibition and cooperative inhibitor binding over the substrate concentration range 0.25–100 μM.

VmaxKnClmaxKiVi
pmol⋅min/pmolμMμMpmol/min per picomoles
CYP2B6.17.4 ± 2.417 ± 81.4 ± 0.30.2547 ± 100.0001 ± 0.42
CYP2B6.46.2 ± 1.09 ± 21.7 ± 0.30.3553 ± 80.0002 ± 0.44
CYP2B6.54.1 ± 0.411 ± 21.2 ± 0.10.2575 ± 105.8e−5 ± 0.42
CYP2B6.63.6 ± 0.213 ± 11.7 ± 0.10.1484 ± 161.46 ± 0.43
CYP2B6.72.7 ± 1.016 ± 121.0 ± 0.20.1746 ± 114.5e−5 ± 0.14
CYP2B6.92.8 ± 0.721 ± 100.9 ± 0.10.1357 ± 94.4e−5 ± 0.15
CYP2B6.175.5 ± 0.513 ± 21.4 ± 0.10.2371 ± 82.8e−5 ± 0.44
CYP2B6.193.5 ± 0.214 ± 21.5 ± 0.10.13173 ± 4487.1e−5 ± 21
CYP2B6.262.1 ± 0.49 ± 41.2 ± 0.30.1556 ± 115.7e−5 ± 0.18