EU and US Regulatory Update – Tykerb/Tyverb® (lapatinib)

Issued: London UK

GlaxoSmithKline announced today that it has submitted regulatory applications in Europe and the US related to Tykerb/ Tyverb (lapatinib) and its use in combination with trastuzumab to treat patients with HER2 (ErbB2)-positive metastatic breast cancer.

• a variation to the Marketing Authorisation Application to the European Medicines Agency for Tyverb (lapatinib) in combination with trastuzumab for the treatment of patients with HER2 (ErbB2)-positive metastatic breast cancer that has progressed on prior trastuzumab regimens.
• a supplemental New Drug Application to the US Food and Drug Administration for Tykerb (lapatinib) in combination with trastuzumab for the treatment of patients with HER2 (ErbB2)-positive metastatic breast cancer who have received prior trastuzumab therapy.

Additionally, GSK announced that it has withdrawn its variation application to the European Medicines Agency for approval to market Tyverb (lapatinib) in combination with paclitaxel for the treatment of patients with metastatic breast cancer whose tumours over-express HER2 (ErbB2). The decision follows an assessment this week from the Committee for Medicinal Products for Human Use (CHMP) that the lack of a direct comparison to trastuzumab plus paclitaxel hampered the proper assessment of the benefit-risk in European patients in the applied indication.

"Tykerb/Tyverb is an important part of the GSK Oncology portfolio and the regulatory submissions in the EU and US for Tykerb/Tyverb in combination with trastuzumab demonstrate our commitment to the field of HER2 positive disease." said Rafael Amado, Senior Vice President, GSK Oncology R&D. "In terms of our submission for Tyverb in combination with paclitaxel, we are disappointed with the CHMP trend vote and have decided to withdraw the application. However, regulatory review of submissions for the combination of Tykerb/Tyverb and paclitaxel in the metastatic breast cancer setting are ongoing in other regions."

Lapatinib was first approved for use in combination therapy in the metastatic setting in 2007 and is currently approved in 107 countries including the U.S., Europe, Australia, India, Brazil, Russia, Turkey, South Korea and other countries around the world. For more information about the currently licensed indications for Tykerb/Tyverb, please visit the Product section of this website to view the Tyverb EU Patient Information Leaflet and full Tykerb US Prescribing Information including BOXED WARNING risk for hepatotoxicity.

GlaxoSmithKline – one of the world’s leading research-based pharmaceutical and healthcare companies – is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For further information please visit www.gsk.com

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GlaxoSmithKline cautionary statement regarding forward-looking statements Under the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995, GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Factors that may affect GSK's operations are described under 'Risk Factors' in the 'Business Review' in the company's Annual Report on Form 20-F for 2010.