GlaxoSmithKline plc (GSK) announced the submission of a Marketing Authorisation Application (MAA) to the European Medicines Agency (EMEA) for approval to market Tykerb (lapatinib ditosylate) in combination with Xeloda (capecitabine), for the treatment of advanced or metastatic ErbB2 (HER2) positive breast cancer in women who have received prior therapy, including Herceptin (trastuzumab).

Lapatinib is a small molecule dual receptor tyrosine kinase inhibitor developed by GSK as an oral therapy, and is currently being investigated in breast cancer and other solid tumours. Lapatinib is an investigational medicinal product and has not been approved for marketing by any regulatory body. GSK announced the submission of a New Drug Application (NDA) to the US Food and Drugs Administration (FDA) on 18th September 2006. By the end of 2006, GSK aims to have also filed lapatinib in Australia, Canada and a number of countries in Asia, Latin America and the Middle East.

Lapatinib is an investigational small molecule that is administrated once daily orally. It inhibits the tyrosine kinase components of ErbB1 (EGFR) and ErbB2 (HER2) receptors. Stimulation of ErbB1 and ErbB2 is associated with cell proliferation and with multiple processes involved in tumour progression, invasion, and metastases. Overexpression of these receptors has been reported in a variety of human tumours and is associated with poor prognosis and reduced overall survival.

"Our filing in the EU is the culmination of many years of committed research and development work by GSK employees around the world. In Europe more than 360,000 new cases of breast cancer are diagnosed every year and approximately 50 percent of these women will go on to develop metastatic disease despite primary treatment. We hope that lapatinib will offer these patients a much needed effective alternative treatment," said Paolo Paoletti, M D, senior vice president of the Oncology Medicine Development Centre at GSK. "This is GSK's third European oncology filing this year, following topotecan (Hycamtin) for relapsed cervical cancer and nelarabine (Atriance) in June, and we are on track for similar announcements to be made in 2007."