Among anti-myeloma agents, dexamethasone is a strong inducer of CYP3A4 and P-glycoprotein and an inhibitor of P-glycoprotein; bortezomib is a CYP3A4 inhibitor; and venetoclax is an inhibitor of P-glycoprotein [96,97]. Here, ABCB1 is linked to plasma cell myeloma.