Study Evaluating the Safety and Efficacy of PTX-022 (QTORIN Sirolimus) in the Treatment of Microcystic Lymphatic Malformations

Inclusion Criteria: * Participants must be 6 years or older * Diagnosed with Microcystic Lymphatic Malformations * Able and willing to comply with all protocol-required activities * Willing and able to provide written informed consent Exclusion Criteria: * Any significant concurrent condition that could adversely affect participation. * Any history of allergy or hypersensitivity to sirolimus, or sirolimus-like medications or to PTX-022 * Patient's deemed by the investigator as unwilling or unable to remain compliant with all tests and procedures, including adherence to study drug administration and other protocol-required activities.