TABLE 2.

The catalytic rate constants (k_cat values) for formation of M2 from trans-ITZ stereoisomers in incubations with reconstituted CYP3A4 and with CYP3A4 Supersomes

Catalytic rates could not be measured for cis-ITZ stereoisomers because of high substrate depletion and formation of M2 from multiple substrates simultaneously.

Trans-	(2R,4R,2′R)-ITZ	(2R,4R,2′S)-ITZ	(2S,4S,2′S)-ITZ	(2S,4S,2′R)-ITZ
kcat, s−1, reconstituted CYP3A4	0.0032 ± 0.0005	0.0038 ± 0.0001	0.0041 ± 0.0007	0.0042 ± 0.0004
kcat, s−1, CYP3A4 Supersomes	0.0159 ± 0.003	0.0214 ± 0.004	0.0183 ± 0.003	0.0198 ± 0.001