NHP-drug and NHP-NHP interactions can be pharmacokinetic or pharmacodynamic, often involving changes in expression or function of the hepatic, extra-hepatic, and potentially tumour-expressed CYP 450 enzymes, which metabolize the majority of anticancer drugs and ATP efflux pumps such as P-glycoprotein, which are involved in drug transport [47, 49–51]. Here, ABCB1 is linked to neoplasm.