Tarceva is an investigational small molecule designed to target the human epidermal growth factor receptor (HER1) pathway, which is one of the factors critical to cell growth in many cancers. HER1, also known as EGFR, is a key component of the HER signalling pathway, which plays a role in the formation and growth of numerous cancers. Tarceva is designed to inhibit the tyrosine kinase activity of the HER1 signalling pathway inside the cell, which may block tumour cell growth. Results of a Phase III trial of Tarceva in pancreatic cancer are expected during the second half of 2004. Early-stage trials of Tarceva are being conducted in other solid tumours such as ovarian, colorectal, head and neck, renal cell carcinoma, glioma and gastrointestinal cancers. Tarceva(TM) was discovered by OSI Pharmaceuticals and is being developed by a global alliance of Roche, OSI Pharmaceuticals and Genentech.

About Non-Small Cell Lung Cancer

According to the World Health Organization, there are more than 1.2 million cases worldwide of lung and bronchial cancer each year, causing approximately 1.1 million deaths annually. Non-small cell lung cancer is the most common form of the disease and accounts for almost 80 percent of all lung cancer.

Roche in Oncology

Within the last five years the Roche Group has become the world's leading provider of anti-cancer treatments, supportive care products and diagnostics. Its oncology business includes an unprecedented four marketed products with survival benefit: Herceptin, MabThera, Xeloda and Avastin which has been launched by Genentech in the US recently, treat a range of malignancies such as breast cancer, non-Hodgkin's lymphoma and colorectal cancer. Other key products include NeoRecormon (anaemia in various cancer settings), Bondronat (prevention of skeletal events in breast cancer and bone metastases patients, hypercalcemia of malignancy), Kytril (chemotherapy and radiotherapy-induced nausea and vomiting) and Roferon-A (leukaemia, Kaposi's sarcoma, malignant melanoma, renal cell carcinoma). CERA is the most recent demonstration of the commitment to anaemia management. Roche's cancer medicines generated sales of more than 6 billion Swiss francs in 2003.

In a recent phase III study Tarceva met its primary endpoint of improving overall survival in patients with non-small cell lung cancer.

Roche is developing new tests, which will have a significant impact on disease management for cancer patients in the future. With a broad portfolio of tumor markers for prostate, colorectal, liver, ovarian, breast, stomach, pancreas and lung cancer, as well as a range of molecular oncology tests, we will continue to be the leaders in providing cancer focused treatments and diagnostics.

Roche Oncology has four research sites (two in the US, Germany and Japan) and four Headquarter Development sites (two in the US, UK and Switzerland).

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Further information: - www.roche - www.gene - www.osip