A panel of experts brought together by the US Food and Drug Administration (FDA) recommended on Sept. 24 that the FDA approve the targeted therapy Iressa for use against lung cancer.

The FDA usually — but not always — gives final approval to drugs recommended for approval by its advisory committees.

The members of these committees include medical professionals, scientists and researchers, industry leaders, consumer representatives, and patient representatives. They carefully review all the evidence on a drug before making a recommendation to the FDA whether a drug can be used in patients.

A final, formal decision by the FDA is expected within 45 to 60 days.

The panel recommended the FDA approve the drug for patients with non-small cell lung cancer (NSCLC) in whom the disease has not responded to at least two chemotherapy agents.

According to the manufacturer of the drug, AstraZeneca, there are no drugs currently approved for patients in this situation.

London-based Astra-Zeneca submitted data from two clinical trials of the drug, showing that about 10% of all patients in one trial conducted in the US responded to the drug. In the other study, which was conducted in Japan and elsewhere, about 11% of Caucasian patients and 28% of Japanese patients responded to the drug.

The side effects were relatively mild and included mainly skin rashes, diarrhea, nausea, and vomiting. There was no hair loss or drop in infection-fighting white blood cells that can be seen with use of many other chemotherapy drugs.

In about 40% of patients, the quality of life was improved by less coughing and other breathing problems, according to the company-provided study data.

Iressa is one of a new class of drugs that are called targeted therapies because they focus their attack on substances that are present or abundant only on or within cancer cells, leaving most normal cells unharmed.

Iressa works against a receptor, or protein, on the surface of certain cancer cells. This protein, called epidermal growth factor receptor (EGFR), causes the cancer cell to divide rapidly, making more cells.

Iressa stops the protein's signals and the rapid production of cancerous cells driven by EGFR. The goal of the treatment is to decrease the number of cancer cells in the body.

Several other kinds of cancer may be driven by EGFR, and Iressa is currently being tested against breast, colorectal, prostate, and head and neck cancers.

A report by the FDA staff released the day prior to the hearing found several problems with the studies. The report also noted that another trial using Iressa in lung cancer had been reported, and this study clearly showed that Iressa had no benefit in improving survival or response rates in patients with lung cancer.

As a result of this report, there had been speculation that the FDA panel would not recommend approval.

But the panel members voted 11-3 to recommend approval of the drug, indicating they believed the help it apparently can offer to some patients with no other options is more important than shortcomings in the studies.

Gerard T. Kennealey, MD, vice president of oncology research for AstraZeneca, said, "The [committee] deliberations were a vote of confidence in Iressa and the clinical benefit we have seen with this drug."

If the FDA approves Iressa, it will be sold as a once daily, 250 mg tablet that can be taken by mouth, according to the company.