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Published on: April 6, 2017
Comparative bioavailability of inhaled treprostinil administered as LIQ861 and Tyvaso® in healthy subjects
Robert F Roscigno1, Toby Vaughn2, Ed Parsley3
1Clinical Development Consultant, Melbourne Beach, FL, USA.
Introduction:
Treprostinil is a synthetic prostacyclin analogue approved for inhalation administration to patients with pulmonary arterial hypertension (PAH) via nebulized Tyvaso® inhalation solution. LIQ861 is an inhaled, dry-powder formulation of treprostinil produced using Print® (Particle Replication in Nonwetting Templates) technology, a proprietary process for designing and producing highly uniform drug particles.
Methods:
We conducted comparative bioavailability analyses of treprostinil exposure from LIQ861 (79.5 μg capsule [approximate delivered dose of 58.1 μg treprostinil]) compared with Tyvaso® (9 breaths [approximate delivered dose of 54 μg treprostinil]).
Results:
Treprostinil exposure parameters had least squares geometric mean ratios (LIQ861: Tyvaso®) between 0.9 and 1.0 with 90% confidence intervals contained within 0.8 to 1.25. LIQ861 and Tyvaso® were both well tolerated.
Discussion:
Results showed comparable bioavailability of treprostinil and similar tolerability for LIQ861 and Tyvaso® administered to healthy adults.
Conclusions:
Given the comparable treprostinil bioavailability and similar safety profiles of LIQ861 and Tyvaso®, LIQ861 fulfills a significant unmet need for PAH patients by maximizing the therapeutic benefits of treprostinil by safely delivering doses to the lungs in 1 to 2 breaths using a discreet, convenient, easy-to-use inhaler.
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