FDA Asked to Approve LIQ861, Treprostinil Dry Powder Inhaler for PAH, Liquidia Announces

Liquidia Technologies is requesting U.S. Food and Drug Administration (FDA) approval of LIQ861, an inhaled dry powder formulation of the vasodilator treprostinil, to treat pulmonary arterial hypertension (PAH).

The request came in the form of a new drug application (NDA) to the agency.

LIQ861 is based on Liquidia’s PRINT Technology, a particle engineering platform that enables the production of highly uniform drug particles with controlled size, shape, and chemical composition of its pharmacological properties. The technology was used to engineer LIQ861 for optimal deep-lung delivery of the medication upon inhalation, the company states.

Its application is supported by data from three clinical studies evaluating the safety, tolerability, and pharmacokinetic profile (distribution and availability in the body) of LIQ861. (Treprostinil works to dilate, or wide, the arteries, effectively lowering blood pressure in the pulmonary artery that leads from the heart to the lungs.)

One of these studies was the open-label Phase 3 INSPIRE trial (NCT03399604)in 121 PAH patients. All were either on a stable dose of inhaled treprostinil (Tyvaso, by United Therapeutics) before switching to LIQ861, or were prescribed to two oral non-prostacyclin therapies when starting with LIQ861 as an add-on therapy.

Results from an earlier preliminary analysis showed that doses of LIQ861 ranging between 25 and 150 micrograms were well-tolerated after two months of treatment, with no serious side effects reported.

Positive trends were also observed in both groups concerning patients’ ability to perform physical activities, and stabilized or improved quality of life.

More recent results indicated that 75 microgram capsule-strength of LIQ861 (delivered in one-to-two inhalations) are therapeutically equivalent to a 54 microgram dose of Tyvaso (nine inhalations), the maximum recommended for treprostinil.

The company also completed pharmacokinetic studies — measure of  the time needed for the therapy’s absorption, distribution and metabolism in the body, and its elimination — to establish the bioavailability of LIQ861 compared to Tyvaso.

“The submission of the NDA for LIQ861 in the U.S. is a significant milestone for our company and our goal to address an important unmet need in the delivery of inhaled therapy for PAH patients. We would like to sincerely thank the patients, their families, and the clinical investigators … and we look forward to working closely with the FDA during the review process,” Neal Fowler, CEO of Liquidia, said in a press release.

According to Liquidia, one of the leading reasons for patient dissatisfaction with Tyvaso is its inconvenience. The therapy can require more than 36 breaths per day using a nebulizer that needs daily set up and cleaning.

LIQ861, in contrast, is “a convenient, palm-sized, disposable dry powder inhaler,” and as such is easy to use while “maximizing the therapeutic benefits” of delivering treprostinil deep into the lungs, the company states.