FRIDAY, May 23 (HealthDay News) -- Patients with a progressive fibrosis of the lungs that's fatal within a few years of diagnosis may finally have some reason for hope.

Japanese researchers say daily use of the drug pirfenidone improved the lung function and lengthened the survival of patients with the illness, called idiopathic pulmonary fibrosis (IPF).

"Patients look to any research in IPF with a sense of hope, because right now, there's very little that can be done for them," said Mark Shreve, founder and chief operating officer of the Coalition for Pulmonary Fibrosis, based in San Jose, Calif.

"To say that there's a desperate need -- even that would be an incredible understatement, because you are talking about a devastating, relentless disease that has a survival rate of less than three years, and no proven cause and no treatment," he said.

But the results of the new phase III clinical trial, involving 275 Japanese patients with mild-to-moderate IPF, may change all that. The findings were presented this week at the annual meeting of the American Thoracic Society, in Toronto.

According to Shreve, 128,000 Americans are battling IPF at any given time. Each year, 48,000 new cases are diagnosed, and 40,000 people die from the illness -- equal to the annual death toll from breast cancer.

IPF's origins remain largely unknown. It typically arises in late middle-age or the senior years and involves a progressive fibrosis: a process in which healthy lung tissue turns into useless scar tissue. This hardening of the lungs gradually and relentlessly robs patients of their ability to breathe.

"There's no drug, period, that's ever been approved for IPF," Shreve said. "Right now, the only treatment option that's been shown to extend the lives of patients is a lung transplant. But, other than that, the disease itself is an incredibly progressive, severe relentless disease."

That's why the results of the new trial have generated a level of cautious excitement among the IPF research community. In the study, a team led by Dr. Takashi Ogura, of Kanagawa Cardiovascular and Respiratory Center, Yokohama, gave patients either high-dose (1,800 milligrams) or low-dose (1,200 milligrams) pirfenidone or a placebo each day. Then they tracked changes in lung capacity, disease progression and patient survival over the course of a year.

Ogura's team reported that patients on high-dose pirfenidone achieved significantly less deterioration in lung capacity compared to those not on the drug. Those placed on the medication also displayed a slowdown in disease progression. Side effects included skin rash and loss of appetite.

"Taken together, our study demonstrated positive clinical effects of pirfenidone that suppresses the progress of IPF and potentially contributes to improving the outcomes of patients with IPF," Ogura said in a prepared statement.

Pirfenidone is "a drug in its own class," explained Dr. Ganesh Raghu, director of the Interstitial Lung Disease/Sarcoid/Pulmonary Fibrosis Program at the University of Washington Medical Center, in Seattle. His team pioneered the use of pirfenidone -- which is thought to have anti-inflammatory and anti-fibrotic properties -- against IPF more than a decade ago.

"It has taken this long -- 11, 12 years -- for it to reach the stage of phase III. I'm quite pleased that a drug of potential efficacy or anti-fibrotic effect is used for IPF. The Japanese trial is encouraging," said Raghu, who is also professor of pulmonary and critical care medicine at the University of Washington.

Still, he stressed that the population used in the Japanese trial may not represent the full spectrum of IPF patients, so it's too early to tell if pirfenidone will work for everyone with the disease. A larger, multi-center trial using the drug is currently under way in Europe and North America, with results expected later this year.

"Until further studies that enroll large number of patients and include all spectrum of patients with IPF, we cannot extrapolate the findings to the entire patient population with IPF," Raghu said.

He also cautioned that pirfenidone has not yet been approved for use against any medical condition by the U.S. Food and Drug Administration, meaning that IPF patients can only get the medicine by participating in a clinical trial.

And while pirfenidone may slow the progression of IPF, it does not stop it, Shreve noted.

"If this drug works out, that's fantastic, but it's still not a cure," Shreve said. "With a cure -- that's when we'll be really excited."

More information

To learn more about IPF, visit the Coalition for Pulmonary Fibrosis.