Lapatinib (INN) or lapatinib ditosylate (USAN) (Tykerb/Tyverb, GSK) is an orally active chemotherapeutic drug treatment for solid tumours such as breast cancer. During development it was known as small molecule GW572016. Patients who meet specific indication criteria may be prescribed lapatinib as part of combination therapy for breast cancer. Pharmacologically, lapatinib...