Source: health.usnews.com
Author: Steven Reinberg

The cancer-fighting pill Iressa works as well as chemotherapy as a second-line treatment for lung cancer, researchers report. Although neither therapy prolongs survival beyond eight months, Iressa (gefitinib) causes fewer serious side effects and may be a better choice for patients who did not do well on their first round of chemotherapy.

“A pill, with less side effects, taken once a day, has similar activity to traditional chemotherapy given by vein every three weeks,” said lead researcher Dr. Edward Kim, an assistant professor at the M. D. Anderson Cancer Center in Houston.

This finding should reassure doctors that they are not compromising effective therapy by using a pill, Kim said. Iressa is not available in the United States, but a similar drug, Tarceva, is.

Iressa was first developed by AstraZeneca, but it failed to meet expectations. The National Cancer Institute ended clinical trials of the drug in 2005 because it failed to prolong the lives of lung cancer patients.

The latest finding has meaning for these patients, however, Kim said. “You can be treated for lung cancer. There are different therapies available, and they have different side-effect profiles,” he said. “Chemotherapy will never be eliminated, but we are getting more options for targeted therapy; and people can live as normal a life as they can bearing the weight of lung cancer.”

The report was published in the Nov. 22 issue of The Lancet.

In a head-to-head comparison, Kim’s team randomly assigned 1,466 lung cancer patients who had undergone previous chemotherapy to daily doses of Iressa or the chemotherapy drug docetaxel once every three weeks.

The researchers found that survival in both groups of patients was about the same. Median survival for those taking Iressa was 7.6 months compared with eight months for patients receiving docetaxel. For patients with an EFGR gene mutation, average survival was 8.4 months for those on Iressa and 7.5 months for those receiving docetaxel.

However, there were significant differences in the side effects experienced by the treatment groups. For patients taking Iressa, the most common side effects were rash or acne. Among patients receiving docetaxel, the most common side effects were a blood disorder called neutropenia, personality disorders, and hair loss.

Dr. Michael Cullen, from the University Hospital Birmingham in the United Kingdom and author of an accompanying journal comment, noted that Iressa works differently than chemotherapy by targeting a receptor that is present in some patient’s cancer cells.

“There are now two options that one can select from for patients in order to offer treatment that helps a bit following failure of first-line chemotherapy,” Cullen said. “Survival overall is very poor, and, in fact, it’s almost certainly the case that only a small minority of patients respond to either of the two treatments.”

In addition, which patients would benefit most from Iressa isn’t known, Cullen said. “In the study, tests didn’t indicate that we are able to select treatment based on different characteristics of the patient.”

Because survival time is short, Cullen thinks that doctors may want to decide which treatment to use based on how well a patient tolerated chemotherapy before.

“If they didn’t tolerate chemotherapy very well, maybe the oncologist would opt for the oral therapy, whereas if they responded well to chemotherapy, the best choice might be to go with the chemotherapy,” Cullen said.