TABLE 5.

Parsing rationale for substrate and inhibitors

Category	Clearance/P450-Glo	Classification	Parsing Rationale
1	+/+	Substrate	Exhibiting activity in both assays, the compound is a clear ligand for the enzyme(s). It is unclear whether the parent, product, or both are responsible for the inhibition.
2	−/+	Inhibitor	The compound is able to inhibit the enzyme metabolism of a probe substrate but is not itself cleared, indicating that the parent molecule is an effective inhibitor.
3	−/−	Noncompetitor	The lack of activity in both assays signifies either that binding does not occur or that the interaction does not generate a catalytically competent or inhibitory complex.
4	+/−	Substrate	Although a clear substrate, the binding kinetics of the parent compound and its metabolites do not preclude the concomitant metabolism of the P450-Glo probe.