The U.S. Food & Drug Administration (FDA) has granted orphan drug designation to Pulmatrix‘s PUR1900, an inhaled drug for the treatment of pulmonary fungal infections in patients with cystic fibrosis (CF).

Orphan drug status is granted to drugs that show a potential to treat rare diseases, effect less than 200,000 people in the U.S., or can help more than 200,000 people but are not expected to provide financial gain for drug companies after development and marketing costs. The designation provides financial incentives for drug companies and a faster regulatory path to market the therapies.

In this case, PUR1900 received the orphan drug designation based on data indicating that the drug may be better than other approved therapies. The status ” is based on a plausible hypothesis that your drug may be clinically superior to the same drug that is already approved for the same indication,” the FDA wrote according to a recent press release.

“This designation is a major boost to our efforts to make this drug available as quickly as possible to cystic fibrosis patients who currently suffer from fungal infections in their lungs, and from the allergic reactions they experience because of the fungal infections,” said Pulmatrix’s Chief Executive Officer Robert Clarke, PhD.

PUR1900 is formulated using Pulmatrix’s proprietary iSPERSE (Inhaled Small Particles Easily Respirable and Emitted) dry powder delivery platform. PUR1900 combines iSPERSE with an existing antifungal drug called itraconazole. The compound can be administered in high therapeutic doses to the lung while minimizing systemic side effects.

“Our technology delivers the drug directly to the lungs,” said David L. Hava, PhD, the company’s chief scientific officer. “That significantly reduces the risks of side effects and drug-drug interactions, bringing great benefits to patients.”

Approximately 50 percent of patients with CF experience pulmonary fungal infections that can cause chronic bronchitis or allergic reactions. This results in inflammation and poor long-term outcomes. As a consequence, patients with CF are often prescribed antibiotics and anti-fungal medications on an ongoing basis in order to curtail the growth of fungi and bacteria.

“The estimated addressable market for improved antifungal treatments for CF is in the tens of thousands or patients per year,” Clarke said. “But the inhaled drug could also find much larger markets treating pulmonary fungal infections and other immunocompromised patients that could expand the addressable market to millions of patients per year.”