В клинично значими концентрации лапатиниб инхибира in vitro CYP3A (Ki 0, 6 до 2, 3 µg/ ml) и CYP2C8 (0, 3 µg/ ml).
Lapatinib inhibits CYP3A (Ki 0.6 to 2.3 µg/ ml) and CYP2C8 (0.3 µg/ ml) in vitro at clinically relevant concentrations.