Treprostinil Earns FDA Orphan Drug Designation for Treating IPF

The U.S. Food and Drug Administration (FDA) has granted treprostinil orphan drug designation for the treatment of idiopathic pulmonary fibrosis (IPF).

Orphan drug designation is given to therapies with the potential to substantially improve treatment for rare diseases (conditions affecting fewer than 200,000 people in the U.S.). The designation makes the medication’s developer,  United Therapeutics, eligible for benefits such as tax credits and FDA funding toward clinical trial costs. The designation also confers seven years of marketing exclusivity in the U.S., if the medication is ultimately approved.

“We’re excited that treprostinil has received orphan drug designation, as it validates our drive to address orphan diseases, like IPF, with a significant unmet need,” Martine Rothblatt, PhD, chairman and CEO of United Therapeutics, said in a press release.

Prostacyclin is a molecule naturally produced by the body that causes blood vessels to dilate (widen), reducing blood pressure. It also helps to prevent blood clots. The active component of treprostinil is a synthetic molecule that mimics the activity of prostacyclin.

In the U.S., treprostinil is approved as an inhaled therapy under the brand name Tyvaso, for treating pulmonary arterial hypertension (PAH), a condition characterized by abnormally high blood pressure in the lung’s blood vessels.

IPF is characterized by scarring (fibrosis) that thickens the tissue of the lungs. The condition specifically refers to pulmonary fibrosis in which there is no clearly identifiable cause for the scarring. Pulmonary hypertension — a broader term for increased blood pressure in the lungs — is a common complication of IPF and other types of pulmonary fibrosis.

A Phase 2 clinical trial called INCREASE (NCT02630316) evaluated the safety and effectiveness of inhaled treprostinil in people with PH-associated interstitial lung diseases, an umbrella term that encompasses IPF and other conditions characterized by lung fibrosis. Results indicated the treatment decreased the frequency of exacerbations (when symptoms suddenly worsen)  and prevented the decline of lung function.

United is now planning to launch a Phase 3 trial, called TETON, to evaluate the use of Tyvaso in people with IPF. The trial already has received clearance from the FDA and is expected to begin enrollment in 2021.

“TETON represents a significant move outside the pulmonary hypertension space, but based on data collected during the recent INCREASE study we’re confident that inhaled treprostinil can help address clinical gaps presented by existing therapies in IPF,” Rothblatt said.