Liquidia Technologies Inc. started an underwritten public offering of 3 million common shares.

The late-stage clinical biopharmaceutical company also plans to grant the underwriters an option to buy up to an additional 450,000 shares at the public offering price.

Jefferies and Cowen are acting as joint book-running managers, with Needham & Co. and Wedbush PacGrow as co-managers for the offering.

Morrisville, N.C.-based Liquidia develops and sells human therapeutics using its proprietary Print technology, a particle engineering platform.

Liquidia's lead product candidate LIQ861 — an inhaled dry powder formulation of treprostinil — is in a phase 3 study to treat pulmonary arterial hypertension.