TABLE 6

Reliability of in vitro systems for metabolic clearance predictions

For each method, in vivo intrinsic clearance values were calculated using the parallel-tube model incorporating the free fraction in blood. In vitro intrinsic clearance values were adjusted for either microsomal or hepatocyte binding using the methods of Gertz and Hallifax.

	Recombinant Enzymes	Microsomes^a	Hepatocytes^a
n	72	41	57
r ²	0.43	0.28	0.40
afe	1.53	2.32	5.21
rmse	1528	3501	3608
% Inside 2-fold error	32	29	18
% Inside 5-fold error	73	66	46

↵ a Data taken from the literature (Stringer et al., 2008).