Palvella Therapeutics (PVLA) said the US Patent and Trademark Office granted it a patent for claims related to the company's Qtorin 3.9% rapamycin anhydrous gel candidate.

The patent provides broad protection through 2038 for anhydrous topical composition and methods of use for the potential microcystic lymphatic malformations treatment, the company said.

The drug has already been granted US and Food Drug Administration breakthrough therapy, orphan drug and fast track designations, the company said.