Boehringer, InterMune wow IPF field with a slate of groundbreaking trial data

The latest download of data on a pair of rival therapies for lethal cases of idiopathic pulmonary fibrosis wowed researchers in the field, producing clear evidence of their ability to slow down the lung disease and offering patients a possible set of game-changing treatments.

Boehringer Ingelheim put up the results for two pivotal studies of nintedanib, both of which registered statistically significant reductions in the rate of lung decline, as measured by a standard yardstick called forced vital capacity, or FVC. Among the more than 1,000 patients in the two studies, the drug arms reflected a drop in the annual rate of FVC decline of 48% and 55%. The placebo arm in both trials, meanwhile, only managed a 5% reduction in FVC decline. The drug works by inhibiting tyrosine kinase inhibitors.

InterMune ($ITMN), meanwhile, demonstrated that patients taking its drug, pirfenidone, did much better than the placebo arm on FVC as well. After a year of therapy, 16.5% of the patients in the drug group had registered a 10% or greater decline in FVC--enough to seriously increase the risk of mortality--compared to 31.8% of the placebo group. Pirfenidone also cleared the bar on a secondary endpoint based on a 6-minute walk test while failing another secondary goal for shortness of breath.

Experts in the field were quick to herald the unprecedented results as groundbreaking, noting that current therapies for IPF can only blunt the symptoms of the disease, rather than change its deadly trajectory. A large group of investors has been tracking every step of the IPF race being run by these two companies. InterMune has seen its share price soar in anticipation of a winning Phase III program. Boehringer has had to deal with some secondary endpoint slips, though its drug remains very promising.

In an editorial accompanying a piece on nintedanib in The New England Journal of Medicine, Brigham & Women's Gary Hunninghake also noted that there were some caveats to consider. All of the patients in these studies were at an early stage of the disease and both drugs appeared to have an equal impact.

"Although these results are a major breakthrough for patients with idiopathic pulmonary fibrosis, we should be cautious in extrapolating these findings to patients who fall outside the recruitment criteria for these trials," Hunninghake wrote. "The studies provide little insight into the use of these drugs in patients with more severe disease (FVC <50% of the predicted value) or with an acute disease exacerbation."

"The study results provide strong evidence of pirfenidone's robust treatment effects and augment its already well-established safety and tolerability profile," sats InterMune CEO Dan Welch. "We currently intend to resubmit the pirfenidone New Drug Application to the U.S. Food and Drug Administration in the coming weeks."

- here's the Boehringer release
- read the release from InterMune