Related Pages Lung Cancer Home Page 1 NCI's gateway for information about lung cancer. Drug Information Summaries 2 NCI's drug information summaries provide consumer-friendly information about certain drugs that are approved by the U.S. Food and Drug Administration (FDA) to treat cancer or conditions related to cancer.

Brand name(s): Iressa®

• Approved for non-small cell lung cancer

Full prescribing information ³ is available, including clinical trial information, safety, dosing, drug-drug interactions and contraindications.

• patients currently receiving and benefiting from gefitinib
• patients who have previously received and benefited from gefitinib
• previously enrolled patients or new patients in non-Investigational New Drug (IND) clinical trials approved by an IRB prior to June 17, 2005

New patients may also be able to obtain gefitinib if AstraZeneca decides to make it available under the IND and the patients meet the criteria for enrollment under the IND.

Gefitinib, an orally administered epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, was approved for marketing in May 2003 for patients with non-small cell lung cancer (NSCLC) under Subpart H accelerated approval regulations that allow products to be approved on the basis of a surrogate endpoint for clinical efficacy. For gefitinib the surrogate end-point was tumor response rate. The response rate in patients taking the drug was approximately 10 percent.

The approved indication was for the treatment of patients who were refractory to established cancer treatments (both a platinum drug and docetaxel). However, since the initial approval of gefitinib, erlotinib (Tarceva™) has been approved for treatment of this same group. Erlotinib was approved based on improved overall survival.

The FDA has carefully reviewed data from two failed clinical studies of gefitinib, one of which was required by the agency as part of the drug's accelerated approval. This trial enrolled patients with regionally advanced or metastatic NSCLC who had failed one or two prior treatment regimens. In this large study, 1,692 patients were given either gefitinib or placebo. There was no significant survival benefit in the overall study population nor in patients who had high levels of a surface marker called "EGFR". In contrast, the presence of EGFR at high levels appears to predict a good response to erlotinib.

In the second trial in patients with stage III NSCLC, after completion of induction and consolidation chemotherapy and radiation therapy, patients were given either gefitinib or placebo maintenance therapy. No gefitinib survival benefit could be demonstrated.

The FDA is not considering market withdrawal of gefitinib at this time. New clinical trials are being developed, other ongoing trials are being completed, and there will be further analysis of the completed trials described above. These will determine the future role of gefitinib treatment.

Glossary Terms

Treatment that is given after cancer has disappeared following the initial therapy. Consolidation therapy is used to kill any cancer cells that may be left in the body. It may include radiation therapy, a stem cell transplant, or treatment with drugs that kill cancer cells. Also called intensification therapy and postremission therapy.

A drug used together with other drugs to treat certain types of breast cancer, stomach cancer, prostate cancer, and certain types of head and neck cancer. It is also being studied in the treatment of other types of cancer. Docetaxel is a type of mitotic inhibitor. Also called Taxotere.

In clinical trials, an event or outcome that can be measured objectively to determine whether the intervention being studied is beneficial. The endpoints of a clinical trial are usually included in the study objectives. Some examples of endpoints are survival, improvements in quality of life, relief of symptoms, and disappearance of the tumor.

In medicine, a sign, symptom, or medical condition that leads to the recommendation of a treatment, test, or procedure.

Initial treatment used to reduce a cancer. Induction therapy is followed by other treatments, such as chemotherapy, radiation therapy, and hormone therapy to get rid of cancer that remains. Also called first-line therapy, primary therapy, and primary treatment.

The spread of cancer from one part of the body to another. A tumor formed by cells that have spread is called a “metastatic tumor” or a “metastasis.” The metastatic tumor contains cells that are like those in the original (primary) tumor. The plural form of metastasis is metastases (meh-TAS-tuh-SEEZ).

An inactive substance or treatment that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo.

A metal that is an important component of some anticancer drugs, such as cisplatin and carboplatin.

In medicine, describes a disease or condition that does not respond to treatment.

The percentage of patients whose cancer shrinks or disappears after treatment.

Describes a mathematical measure of difference between groups. The difference is said to be statistically significant if it is greater than what might be expected to happen by chance alone. Also called significant.