FDA Issues CRL for Pulmonary Arterial Hypertension Inhalation Powder

The US Food and Drug Administration (FDA) has issued a complete response letter (CRL) for treprostinil (LIQ861) inhalation powder for the treatment of pulmonary arterial hypertension (PAH).

The FDA requested additional information and clarification on chemistry, manufacturing and controls (CMC) data about the drug product and device biocompatibility before approving a New Drug Application (NDA) submitted by Liquidia Technologies.

In addition, the agency reconfirmed the need to conduct on-site pre-approval inspections (PAIs) of 2 of the company’s manufacturing facilities. The FDA stated they have been unable to conduct the inspections during the initial review cycle because of coronavirus disease 2019 (COVID-19) related travel restrictions.

While these issues remain, the FDA did not cite the need for further clinical studies or require additional studies related to toxicology or clinical pharmacology. Liquidia has indicated they plan on addressing the concerns raised in the CRL without delaying the projected launch of the treatment in the second half of 2022.

“We remain very confident in LIQ861 and are committed to working closely with the FDA to address these items to support its approval,” Neal Fowler, Chief Executive Officer at Liquidia, said in a statement. “With more than 70 patients now having received LIQ861 for more than two years in our clinical trials, Liquidia remains committed to PAH patients who we believe are underserved with currently available treatment options.”

Treprostinil is an investigational inhaled dry powder designed using Liquidia’s PRINT technology, which enables the development of drug particles that are precise and uniform in size, shape, weight, and composition.

The application is based on the positive results from the INSPIRE study, an open-label, multi-center phase 3 clinical trial of patients diagnosed with PAH.