PRESS RELEASE: Merck Serono to Reconsider Development of Matuzumab in Metastatic Colorectal Cancer Patients

Merck Serono to Reconsider Development of Matuzumab in Metastatic Colorectal Cancer Patients

DARMSTADT, Germany, August 29, 2007 - Merck Serono, a division of Merck KGaA, announced today that a phase II trial investigating the humanized monoclonal antibody matuzumab in combination with irinotecan in patients with metastatic colorectal cancer (mCRC) who had already failed on multiple prior treatments, including irinotecan, has not met its predefined endpoint of activity. Merck Serono is therefore reconsidering further development of matuzumab in mCRC at this stage.

Matuzumab is currently being co-developed and co-commercialized via a partnership between Merck Serono and Takeda. Both companies share the view that the study results in mCRC do not meet expectations. The companies are, however, continuing to study the drug in other tumors including non-small cell lung cancer (NSCLC).

More than 370,000 people develop colorectal cancer in Europe every year, accounting for 13% of the total cancer burden and around 200,000 deaths.1 Approximately 25% of patients present with metastatic disease.2 Five-year survival rates for patients with mCRC are as low as 5%.3

Merck is a global pharmaceutical and chemical company with sales of EUR 6.3 billion in 2006, a history that began in 1668, and a future shaped by 35,214 employees in 63 countries. Its success is characterized by innovations from entrepreneurial employees. Merck's operating activities come under the umbrella of Merck KGaA, in which the Merck family holds an approximately 70% interest and free shareholders own the remaining approximately 30%. In 1917 the U.S. subsidiary Merck & Co. was expropriated and has been an independent company ever since.