UPDATE 1-US FDA still reviewing Liquidia's inhaled blood pressure drug

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Jan 25 (Reuters) - The U.S. Food and Drug Administration is still reviewing Liquidia's drug to treat a progressive blood vessel disorder related to a lung condition, the company said on Thursday.

The FDA was expected to make its decision by Wednesday, but it is still reviewing Liquidia's marketing application for possible approval, although it has not asked for any additional clinical data to support the application.

The North Carolina-based company was seeking the health regulator's nod to expand the use of its drug to also treat pulmonary hypertension associated with interstitial lung disease (PH-ILD), a group of disorders that cause scarring in the lungs.

The drug was granted tentative approval in 2021 to treat pulmonary arterial hypertension (PAH) to improve adult patients' ability to exercise.

However, Liquidia cannot market the drug in the United States due to a regulatory stay related to a patent infringement dispute with United Therapeutics. (Reporting by Sneha S K and Sriparna Roy in Bengaluru; Editing by Krishna Chandra Eluri and Savio D'Souza)