The US Food & Drug Administration (FDA) has granted orphan drug status for Pulmatrix Inc's inhaled drug for treating pulmonary fungal infections in cystic fibrosis (CF)  patients, named PUR1900.

"Your designation 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 writes.

Special orphan drug status is reserved for promising drugs to treat rare diseases or conditions, and provides both a quick regulatory path to market and financial incentives for companies developing the drugs.

"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," says Pulmatrix CEO Robert Clarke, PhD.

Pulmatrix's PUR1900 combines an existing antifungal drug, itraconazole, with the company's innovative dry powder iSPERSE technology, enabling patients to easily inhale the drug deep into their lungs where it's needed. Recent studies have shown that, taken orally, itraconazole is effective in treating allergic reactions in CF patients who have fungal lung infections. However, high oral doses are needed to get enough of the antifungal drug to the lungs through the bloodstream. That causes severe side effects that must be managed and monitored—including liver toxicity.

"Our technology delivers the drug directly to the lungs," explains Pulmatrix's chief scientific officer, David L. Hava, PhD. "That significantly reduces the risks of side effects and drug-drug interactions, bringing great benefits to patients."

"The estimated addressable market for improved antifungal treatments for CF is in the tens of thousands or patients per year," says Dr. Clarke, "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."

Pulmatrix is a clinical stage biopharmaceutical company developing innovative inhaled therapies to address serious pulmonary disease using its patented iSPERSE technology.