IRESSA (gefitinib) is a once-daily 250mg oral medication that targets and blocks the activity of the EGFR-TK, an enzyme that regulates intracellular signalling pathways implicated in cancer cell proliferation and survival. Growth factor signalling has been identified as a key driver of tumour growth and spread in a wide range of cancers.
IRESSA is designed to specifically target the tumour in a unique way with no need to use maximum tolerated dose.
Studies have shown that tumours with an EGFR mutation are particularly sensitive to IRESSA.1,2 A mutation in the EGFR is a characteristic occurring in about 10-15% of non-small cell lung cancers (NSCLC) in Europe and around 30-40% in Asia.3,4,5,6
In Japan in 2002, IRESSA was the first EGFR-TK inhibitor to be approved for use in lung cancer. It is an established, widely used and valued advanced NSCLC treatment in the pre-treated setting in Japan and Asia.
On the 1st July 2009 the European Commission granted marketing authorisation for IRESSA for the treatment of adults with locally advanced or metastatic NSCLC with activating mutations of EGFR-TK across all lines of therapy. This authorisation is based on two pivotal phase III studies comparing IRESSA with chemotherapy, IPASS1 and INTEREST8.
Safety and Side Effects
To date, over 300,000 patients have been treated with IRESSA. It is generally well-tolerated with the most common adverse events being mild-to-moderate skin rash and diarrhoea (CTC grade 1 or 2). It is not typically associated with the cytotoxic side-effects commonly seen with chemotherapy.9,10,11For more detailed information about safety, please see the Gefitinib Product Information.References
1. Mok TS et al. Gefitinib or carboplatin-paclitaxel in pulmonary adenocarcinoma. New Engl J Med 2009; 361: 947-957.2. Sequist LV. et al. First-line gefitinib in patients with advanced non-small cell lung cancer harbouring somatic EGFR mutations. Journal of Clinical Oncology; 26: 2442-2449. 2008.
3. Cortes-Funes H et al. Epidermal growth factor receptor activating mutations in Spanish gefitinib-treated non-small-cell lung cancer patients. Annals of Oncology. 16(7);1081-1086. 2005.
4. Rosell R, Moran T, Queralt C et al, Screening for epidermal growth factor receptor mutations in lung cancer, New England Journal of Medicine; 361: 958-967. 2009.
5. Tokumo M.et al. The relationship between epidermal growth factor receptor mutations and clinicopathologic features in non-small cell lung cancers. Clinical Cancer Research: 11; 1167-1173. 2005.
6. Yoshida K.et al. Prospective validation for prediction of gefitinib sensitivity by epidermal growth factor receptor gene mutation in patients with nonsmall cell lung cancer. Journal of Thoracic Oncology: 2(1); 22-28. 2007)
7. AstraZeneca Expanded Access Programme (EAP) 2000.
8. Kim ES et al. Gefitinib versus docetaxel in previously treated non-small-cell lung cancer (INTEREST): a randomised phase III trial. Lancet 2008;(372):1809-1818.
9. Tokumo M.et al. The relationship between epidermal growth factor receptor mutations and clinicopathologic features in non-small cell lung cancers. 2005: 1167-1173.
10. Thatcher,N. et al. Gefitinib plus best supportive care in previously treated patients with refractory advanced non-small-cell lung cancer: results from a randomised, placebo-controlled, multicentre study (Iressa Survival Evaluation in Lung Cancer). Lancet 2005; 366(9496):1527-1537.
11. Forsythe, B and Faulkner, K. Drug Safety 2004; 27: 1081-1092.
