Palvella Therapeutics (Nasdaq: PVLA) announced that the U.S. Food and Drug Administration has granted rolling review for the company's New Drug Application for QTORIN rapamycin, intended as a treatment for microcystic lymphatic malformations.

Rolling review is an FDA regulatory feature available to programs with Fast Track or Breakthrough Therapy designation. It allows a company to submit completed sections of an NDA as they become available, enabling the FDA to begin its review before the full application is submitted. Palvella said it expects to complete the NDA submission in the second half of 2026.

QTORIN rapamycin has received Breakthrough Therapy, Orphan Drug, and Fast Track designations from the FDA for the treatment of microcystic lymphatic malformations. According to the company, there are no FDA-approved treatments for the condition, which it estimates affects more than 30,000 people in the United States.

Microcystic lymphatic malformations are a rare genetic disease involving malformed lymphatic vessels that can protrude through the skin, cause persistent leaking and bleeding, and lead to recurrent infections and hospitalization. The condition is described as persistent and progressive.

QTORIN rapamycin is designed to deliver rapamycin directly to affected skin tissue to inhibit mTOR signaling locally while limiting systemic exposure. The drug remains investigational and has not been approved by the FDA or any other regulatory agency.

Wes Kaupinen, founder and chief executive officer of Palvella Therapeutics, said in a statement that the company intends to use the rolling review, along with its Breakthrough Therapy and Fast Track designations, to support "an efficient path toward potential approval."