TABLE 3

Summary of literature examples describing drug-metabolizing enzyme profiling of human tissue biopsy samples following an inhibitor

Inhibitor	Dose, mg (days)	Tissue Biopsy	% Inhibition	Measurement	Target	Reference
Clarithromycin	500, every 12 h (7)	Duodenal (pre- vs. post-)	No change	Protein expression	CYP3A4	Pinto et al., 2005a
Clarithromycin	500, every 12 h (7)	Duodenal (pre- vs. post-)	74%	Activity^{^a}	CYP3A4	Pinto et al., 2005a
Clarithromycin	500, every 12 h (8)	Duodenal (serial)	No change	Protein expression	CYP3A4	Quinney et al., 2013
Clarithromycin	500, every 12 h (8)	Duodenal (serial)	64%–72%	Activity^{^a}	CYP3A4	Quinney et al., 2013
Diltiazem	120, every 12 h (7)	Duodenal (placebo vs. treated group)	No change	mRNA expression	CYP3A4	Pinto et al., 2005b
			No change	Protein expression
			62%	Activity^{^a}