Palvella Therapeutics Announces Positive Topline Results from Phase 2 Study for Microcystic Lymphatic Malformations

Microcystic Lymphatic Malformations (Microcystic LM) is a rare, chronically debilitating genetic disease caused by dysregulation of the PI3K/mTOR pathway. It is characterized by localized masses of malformed lymphatic vessels that protrude through the skin barrier, leading to persistent lymph fluid leakage (lymphorrhea), bleeding, and recurrent serious infections. Currently, there are no FDA-approved treatments for the estimated more than 30,000 individuals living with Microcystic LM in the U.S.

Phase 2 Study Results:

• Efficacy: All twelve participants demonstrated improvements on the PGI-C and CGI-C scales, with all rated as either 'Much Improved' or 'Very Much Improved' by clinicians after twelve weeks of treatment with QTORIN™ rapamycin.
• Safety: QTORIN™ rapamycin was generally well-tolerated, with the most common adverse events being application site pain and pruritus. No drug-related serious adverse events were reported, and no rapamycin was detected in the systemic circulation.
• Future Steps: Palvella completed an End of Phase 2 Meeting with the FDA in February 2023 and anticipates potentially initiating a pivotal Phase 3 study in the second half of 2023. The FDA has granted Orphan Drug and Fast Track Designations to QTORIN™ rapamycin for the treatment of Microcystic LM.

Expert Opinion: James Treat, MD, a pediatric dermatologist at Children’s Hospital of Philadelphia and study investigator, highlighted the daily challenges faced by individuals with Microcystic LMs and the inadequacy of current treatments. He expressed optimism about the potential of QTORIN™ rapamycin to address the underlying mechanisms of the disease.

About Palvella Therapeutics: Palvella Therapeutics is a late clinical-stage biopharmaceutical company focused on developing and commercializing novel therapies for serious, rare genetic skin diseases. The company's lead product candidate, QTORIN™ rapamycin, is in late-stage clinical development for several conditions, including Microcystic LM. QTORIN™ rapamycin has received FDA Fast Track Designation for multiple indications.

Note: QTORIN™ rapamycin is for investigational use only and has not been approved or cleared by the FDA or any other regulatory agency. The safety or efficacy has not been established for any use.