gefitinib, (Iressa discontinued in the US)

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GENERIC NAME: gefitinib



On September 9, 2011 Astrazeneca announced that Iressa will no longer be available in the United States. It had received an expedited approval by the U.S. Food and Drug Administration; however, subsequent clinical trials did not confirm Iressa's clinical benefits. Patients may still obtain Iressa via clinical trials. For more information contact Astrazeneca's information center at 1-800-601-8933.

DRUG CLASS AND MECHANISM: Gefitinib is a drug that is used to treat several types of lung cancer. It works by preventing lung cancer cells from growing and multiplying. Many cells, including cancer cells, have receptors on their surfaces for epidermal growth factor (EGF), a protein that is normally produced by the body and that promotes the growth and multiplication of cells. When EGF attaches to epidermal growth factor receptors (EGFRs), it causes an enzyme called tyrosine kinase to become active within the cells. Tyrosine kinase triggers chemical processes that cause the cells, including cancer cells, to grow, multiply, and spread. Gefitinib attaches to EGFRs and thereby blocks the attachment of EGF and the activation of tyrosine kinase. This mechanism for stopping cancer cells from growing and multiplying is very different from the mechanisms of chemotherapy and hormonal therapy. Gefitinib was approved by the FDA in May 2003.

Medically Reviewed by a Doctor on 7/9/2015

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