Test results buoy researchers studying new cancer drug

? A once-a-day pill that slows cancer by jamming its internal growth signals shows encouraging benefits in terminally ill lung cancer patients, quickly easing symptoms for many.

Research released Saturday showed that the drug, called Iressa, can shrink tumors in some patients who have failed all other therapy. But perhaps even more important for these patients, it relieves cancer symptoms in one-third or more of cases.

The drug, not yet approved for routine use, is one of the new class of so-called targeted therapies that works by specifically interfering with cancer rather than all fast-growing tissue, as standard chemotherapy does. As a result, it carries far fewer side effects, and patients often can safely take it for months or even years.

Many experts doubt that Iressa and drugs like it will actually cure cancer alone, but they say it may help hold the disease in check especially if given in early stages.

“This is a whole new way of treating lung cancer,” said Dr. Mark Kris of Memorial Sloan-Kettering Cancer Center in New York. “People didn’t think this would work. It’s nothing short of amazing.”

The data from the study, financed by drug manufacturer AstraZeneca, were made public by Kris at a meeting of the American Society of Clinical Oncology in Orlando.

In December, AstraZeneca applied for Food and Drug Administration approval to sell Iressa based on this and a similar study released in November. Meanwhile, two much larger studies are under way to test whether the drug can prolong survival when given as first-line therapy to people newly diagnosed with spreading lung cancer.

Kris said the drug was particularly striking for easing symptoms quickly. Most who responded began to feel better within two weeks. The drug relieved their shortness of breath, coughs, poor appetites and other cancer symptoms.

All the people studied had already failed to get better after receiving two different regimens of drugs for their spreading lung cancer. Treatment responses of any kind are rare in people with disease this advanced.

The volunteers’ symptom relief lasted an average of seven months. About one-quarter of the patients enrolled in the study are still alive after 18 months of treatment.

Dr. Karen Kelly of the University of Colorado said symptom relief ranged from moderate to dramatic. “The patients felt the improvement was significant to them. It translated to a better quality of life,” she said.