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Feb 25 (Reuters) - InterMune Inc's lead drug reduced the progression of a fatal lung disease in a late stage trial, inching closer to U.S. approval and almost tripling the company's shares.
The latest trial data brings the world's biggest drugs market closer for InterMune's pirfenidone, a medicine already in use in Europe, Canada and Asia.
Pirfenidone was rejected by the U.S. Food and Drug Administration in May 2010, citing lack of data to prove its effectiveness in treating idiopathic pulmonary fibrosis (IPF), a potentially fatal lung disease.
The health regulator asked InterMune to conduct a new trial to support the drug's U.S. marketing clearance.
The late-stage trial showed that after a year of treatment, 16.5 percent of patients in the pirfenidone group experienced disease progression, around half the level of those using a placebo.
The study also showed that 22.7 percent of patients getting the drug experienced no decline in lung function, more than double the 9.7 percent seen among those taking the placebo.
Pirfenidone had a favorable safety profile and was generally well tolerated, InterMune said.
InterMune earlier tested pirfenidone in two late-stage trials with mixed results. The first trial failed, while the second met its targets.
The drug is already approved to treat IPF in Europe and Canada, where it is marketed as Esbriet. It is also approved in Japan, South Korea, China, India, Argentina and Mexico.
IPF is an irreversible condition that leads to progressive loss of lung function due to scarring, which hinders a lung's ability to absorb oxygen.
InterMune said it expected to resubmit its marketing application for the drug to the FDA by early third quarter of this year.
Germany's Boehringer Ingelheim is also developing a drug for treating IPF and the company is expected to present data from a late-stage trial of the drug later this year.
InterMune's shares jumped as far as $37.22, their highest since July 2011, before easing back a bit on the Nasdaq to $31.70 -- still more than double their closing price of $13.96 on Monday. (Reporting by Esha Dey in Bangalore; Editing by Kirti Pandey and Rodney Joyce)