MannKind Corp. and United Therapeutics have reached a milestone in their licensing and collaboration agreement with a new drug application submitted to the U.S. Food and Drug Administration for the partnership’s pulmonary arterial hypertension treatment.

Called Tyvaso DPI, the inhalable dry powder of treprostinil (TreT) uses MannKind’s inhalation technology first commercialized for delivery of Afrezza, the Westlake Village company’s inhalable insulin.

The partnership is also working on a Bluetooth-connected accessory for the Tyvaso DPI inhaler called BluHale, which monitors inhaler use through a mobile application.

Tyvaso is also intended for patients with pulmonary hypertension associated with interstitial lung disease, MannKind said. The condition causes scarring and inflammation of tissue surrounding the lung’s air sacs, blood vessels and airways. There are currently about 30,000 treatable cases of the condition in the U.S.

Maryland-based United Therapeutics applied for a priority review voucher through the FDA, which could lead to an early decision in December.

“We are excited to see the second compound formulated with our technology complete a rigorous clinical development program,” Michael Castagna, chief executive of MannKind, said in a statement, referring to Afrezza, which uses the same inhaler technology. “If approved by the FDA, Tyvaso DPI is expected to provide a major advancement in the delivery of inhaled treprostinil.”

Shares of MannKind (MNKD) closed Monday down 2 cents, or less than a percent, to $4.16 on the Nasdaq on a day that market closed down nearly 1 percent.