FDA Requests More Data to Support LIQ861’s Potential Approval for PAH

The U.S. Food and Drug Administration (FDA) determined that additional data is required to support the potential approval of LIQ861, Liquidia Technologies’ investigational inhaled formulation of treprostinil, for the treatment of pulmonary arterial hypertension (PAH).

The U.S. agency issued a complete response letter to the company’s previous request for approval — in the form of a new drug application (NDA) — explaining that in its current state, the therapy’s NDA cannot be approved.

In its response letter, the FDA identified the need for additional information about the therapy’s chemistry, manufacturing, and controls data, as well as the biocompatibility of the portable device used to administer the medication.

Yet, Liquidia is confident these concerns may be addressed without delaying the therapy’s estimated launch in the country, or preventing it from being approved as a treatment for PAH. Pending FDA approval, LIQ861 is expected to launch in the second half of 2022 in the U.S.

“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, CEO at Liquidia, said in a press release.

“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,” Fowler added.

The FDA also restated in its letter that it will have to perform on-site pre-approval inspections at two of Liquidia’s U.S. manufacturing facilities before clearing LIQ861’s NDA. So far, the agency has been unable to conduct these inspections due to travel restrictions imposed by the COVID-19 pandemic.

Importantly, the FDA did not request in its response letter to the company that additional clinical, toxicology, or pharmacology studies be carried out to support the therapy’s NDA.

LIQ861 is a dry powder formulation of treprostinil, a vasodilator compound that promotes blood vessel relaxation and widening, thereby lowering blood pressure.

The therapy is based on the company’s proprietary PRINT technology that enables the production of highly uniform drug particles to enhance and optimize its delivery to the lungs. LIQ861 is administered with the help of a user-friendly, portable inhaler.

The therapy’s NDA submission was supported by data from the Phase 3 INSPIRE trial (NCT03399604), which showed LIQ861 was safe and well-tolerated, and able to improve exercise capacity and quality of life in adults with PAH.