This study looks at whether a medication called sirolimus can help slow down the progression of a lung disease called Lymphangioleiomyomatosis (LAM). Sirolimus is a drug that may help by preventing the disease from getting worse. The study is for women aged 18 and older, who have been diagnosed with LAM and have good lung function. Participants will take either sirolimus or a placebo, which is a pill with no medicine, for 2 years. Every 4 months, they will have tests to check how their lungs are working.

The study aims to see if sirolimus can keep the lungs in good shape over time. It is important that participants do not have any other serious health problems or are planning to become pregnant during the study. This study is managed by the LAM Foundation and will take place in clinics around the country.

• The study lasts for 2 years with check-ups every 4 months.
• Sirolimus or placebo will be taken daily.
• Participants must have a diagnosis of LAM and be in good overall health.