InterMune will resubmit its idiopathic pulmonary fibrosis drug pirfenidone to regulators in the USA "in the coming weeks" on the back of successful late-stage data.

The company reported results from the closely-watched Phase III ASCEND study at the American Thoracic Society meeting in San Diego, which showed that pirfenidone significantly reduced decline in lung function. The company noted that "significant treatment effects" were demonstrated on both of the key secondary endpoints of change in six-minute walk distance and progression-free survival.

InterMune added that in a pre-specified analysis of the pooled population from ASCEND and two earlier Phase III trials from the CAPACITY programme showed that the risk of all-cause mortality was reduced by 48% at week 52 in the pirfenidone group compared to placebo.

The drug was approved in Europe in February 2011 as Esbriet and Giacomo di Nepi, managing director of InterMune Europe, told PharmaTimes that it is reimbursed in 14 out of 15 countries on the old continent, priced at 25-30,000 euros. However the road to approval in the USA has been much rockier.

The Food and Drug Administration rejected pirfenidone in May 2010 despite the agency's Pulmonary-Allergy Drugs Advisory Committee voting 9-3 to recommend approval two months earlier. Now most observers believe that the addition of the ASCEND data should be sufficient for pirfenidone to get the green light.

The data came out at the same time as equally impressive results were presented by Boehringer Ingelheim on its IPF offering nintedanib. The two drugs are causing much excitement in a disease area of clear unmet clinical need and Talmadge King of the University of California, San Francisco, who presented the ASCEND results, told PharmaTimes that to have worked for years with no treatments to having two effective drugs is a major advance.

Investors are certainly impressed with InterMune's position and the firm's shares leapt 13.4% to close at $38.92. A number of analysts believe the company has now become an attractive takeover target.

there IPF specialists questioned by PharmaTimes at the ATS meeting would not be drawn on which treatment will become the market leader. Boehringer has yet to reveal when it plans to file.