InterMune's pirfenidone has been awarded 'Breakthrough' status in the US, granting the drug an expedited review as a treatment for the lung scarring disease idiopathic pulmonary fibrosis (IPF).

The move comes hot on the heels of a Breakthrough designation for Boehringer Ingelheim's rival IPF drug nintedanib, and both have also bagged a priority review, leaving them neck and neck in the race to get the first IPF therapy in the US to market.

Idiopathic pulmonary fibrosis (IPF) is an irreversible and ultimately fatal disease characterised by progressive loss of lung function due to fibrosis (scarring) in the lungs, which hinders the ability of lungs to absorb oxygen. The disease affects around 132,000 Americans.

Pirfenidone is an orally active, anti-fibrotic agent that inhibits the synthesis of TGF-beta, a chemical mediator controlling many cell functions including proliferation and differentiation, and plays a key role in fibrosis. The drug - which was approved under the trade name Esbriet in Europe back in 2011 - also inhibits the synthesis of TNF-alpha, a cytokine that is known to have an active role in inflammation.

"The Breakthrough Therapy Designation underscores the significant need to help patients with this irreversible and ultimately fatal disease, particularly as no FDA-approved therapies are currently available," said Dan Welch, Chairman, Chief Executive Officer and President of InterMune.