This clinical trial is focused on studying a condition known as Interstitial Lung Disease (ILD), which involves inflammation and scarring of the lung tissue. The study aims to evaluate the effectiveness and safety of a medication called Rituximab in patients with progressive ILD that has an inflammatory component. Rituximab is a medication that targets specific cells in the immune system and is administered through direct intravenous injection. The study will compare the effects of Rituximab to a placebo, which is a substance with no active medication, to see how it impacts lung function over a period of six months.

Participants in the study will receive two infusions of either Rituximab or a placebo. The main goal is to observe changes in lung function, specifically the Forced Vital Capacity (FVC), which measures the amount of air a person can exhale after taking a deep breath. The study will also monitor other health indicators, such as physical activity levels, respiratory symptoms, and any side effects that may occur during the treatment period. The trial is designed to provide valuable information on whether Rituximab can help improve lung function and quality of life for people with this type of lung disease.

Throughout the study, participants will undergo various assessments, including questionnaires about their symptoms and quality of life, as well as tests like the six-minute walk test to measure physical endurance. Additionally, blood tests will be conducted to evaluate changes in certain biological markers related to the immune system. The study will also track any adverse events, particularly infections, to ensure the safety of the participants. The findings from this trial could potentially lead to better treatment options for individuals with progressive Interstitial Lung Disease.