Iressa Tied To More Pneumonia

[MJ]

TOKYO AUG 25, 2004 (Reuters) - AstraZeneca Plc. said on Wednesday a new study in Japan showed a higher rate of a potentially fatal side effect in patients taking its lung cancer pill Iressa than that demonstrated in an earlier analysis.

The Anglo-Swedish drug maker launched Iressa to treat terminally ill lung cancer patients in July 2002, but the medicine has been linked to the death of 444 patients up to March this year.

The problem has prompted a series of probes in Japan, where the incidence of interstitial pneumonia in patients taking the drug has been significantly higher than elsewhere.

The new 10-month study involving 3,322 lung cancer patients found 5.8 percent of them suffered interstitial pneumonia within eight weeks of starting treatment with Iressa, with a mortality rate of 2.3 percent due to the pneumonia. An earlier study in March 2003, based on 152 Japanese patients on Iressa, had found 1.9 percent had interstitial pneumonia and had estimated the mortality rate at 0.6 percent.

The frequency differs substantially from the global experience with Iressa, with interstitial pneumonia reported in 0.3 percent of patients outside Japan, the company added.

The latest study, which comes as part of an effort to improve Iressa's image, ran from June 2003 to March 2004 on patients who were unable to tolerate surgery or were suffering recurrence of non-small-cell lung cancer.

The company said the latest data was more reliable since it was collected from a larger number of patients.

"We don't think the result means that there has been an increase in the incidence of side effects, but rather that we are getting a more accurate picture," said Masuhiro Kato, senior vice president of Japanese unit AstraZeneca K.K.

The company plans to revise its explanatory note for Iressa to reflect the result of the investigation after consulting with the Health Ministry, it said.

But it has no intention of restricting availability of the drug and believes the clinical benefits of Iressa outweigh the risks.

The reason for the high rate of side effects in Japan remains unclear but AstraZeneca said interstitial pneumonia was associated with all lung cancer therapies, as well as with lung cancer itself.

The drug was launched first in Japan and has since been approved in 29 countries, including the United States. It has been taken by 170,000 patients globally, of which one-third were Japanese, Kato said.

In June, AstraZeneca said its research showed 30 percent of patients with non-small-cell lung cancer taking Iressa were still alive one year after starting treatment.