Phase I dose-escalation and pharmacokinetic trial of lapatinib (GW572016), a selective oral dual inhibitor of ErbB-1 and -2 tyrosine kinases, in Japanese patients with solid tumors.

Objective: The Phase I dose-escalation study was conducted to evaluate the safety and pharmacokinetics of lapatinib (GW572016), a dual ErbB-1 and -2 inhibitor, in Japanese patients with solid tumors that generally express ErbB-1 and/or overexpress ErbB-2.

Methods: Patients received oral lapatinib once daily until disease progression or in an event of unacceptable toxicity.

Results: Twenty-four patients received lapatinib at dose levels of 900, 1200, 1600 and 1800 mg/day; six subjects enrolled to each dose level.