Table 1.
Results of comparison of probe substrate : metabolite ratios for each of the probes used in Study 1.
| Probe substrate and metabolite | CYP | Parameter | Treatments compared | Ratio | 90% CI | P value |
|---|---|---|---|---|---|---|
| Caffeine | 1A2 | AUClast | 4-DC/6-DC | 0.99 | (0.90, 1.09) | 0.899 |
| Paraxanthine | ||||||
| Chlorzoxazone | 2E1 | AUClast | 4-DC/6-DC | 0.87 | (0.71, 1.07) | 0.248 |
| 6-OH chlorzoxazone | ||||||
| Debrisoquine | 2D6 | Ae | 4-DC/6-DC | 0.95 | (0.71, 1.26) | 0.746 |
| 4-OH debrisoquine | ||||||
| Diclofenac (DCL) | 2C9 | Ae | DCL Alone/6-DC | 1.14 | (0.82, 1.58) | 0.480 |
| 4-OH diclofenac | ||||||
| Mephenytoin | 2C19 | Ae | 4-DC/6-DC | 1.04 | (0.84, 1.28) | 0.774 |
| 4-OH mephenytoin | ||||||
| Midazolam | 3A | AUClast | MDZ Alone/6-DC | 1.82 | (1.48, 2.23) | < 0.001 |
| 1-OH midazolam | ||||||
Parameter is the measure used in the calculation of the metabolite/probe ratio for each treatment with the exception of mephenytoin for which absolute values of urinary excretion of the 4-hydroxy metabolite were used as the assay was not stereospecific and hence concentrations of S-mephenytoin could not be measured.