Lapatinib
[5] In March 2007, the U.S. Food and Drug Administration (FDA) approved lapatinib in combination therapy for breast cancer patients already using capecitabine (Xeloda).[5] Pharmaceutical company GlaxoSmithKline (GSK) markets the drug under the proprietary names Tykerb (mostly U.S.) and Tyverb (mostly Europe and Russia).[6] The drug currently has approval for sale and clinical use in the US,[4][6] Australia,[4] Bahrain,[4] Kuwait,[4] Venezuela,[4] Brazil,[7] New Zealand,[7] South Korea,[7] Switzerland,[6] Japan, Jordan, the European Union, Lebanon, India and Pakistan.[4] Like sorafenib, lapatinib is a protein kinase inhibitor shown to decrease tumor-causing breast cancer stem cells.Early clinical trials have been performed suggesting that high dose intermittent lapatinib might have better efficacy with manageable toxicities in the treatment of HER2-overexpressing breast cancers.