Background:~Pulmonary alveolar proteinosis (PAP) is a rare disorder characterized by accumulation of lipoproteinaceous material within alveolar spaces, leading to respiratory failure. Whole lung lavage (WLL) is the current therapeutic option, but it may induce complete resolution of the disorder only in 30% of patients. Based on PAP pathophysiology, a few pilot studies dealing with administration of rGM-CSF (Sargramostim) to patients either s.c. or aerosolized have been performed, with hopeful results.Objectives. We designed an experimental, randomized by parallel groups, stratified according to previous treatment, open-label study looking at evaluation the superiority of the combination WLL/inhaled GM-CSF vs WLL alone in PAP patients. The study also includes a side, observational section. The primary efficacy objective is the total resolution of the pulmonary involvement in all treated patients. The study includes some secondary efficacy objectives as well: avoidance of disease recurrence, avoidance of respiratory infections, investigation of biomarkers predicting the disease outcome, effect of treatments on underlying pathophysiology of PAP.~Methods:~PAP patients matching the enrollment criteria will enter the study. 1) If requiring the first WLL, they will be randomized to receive WLL (1st level control group) or WLL/ followed by inhaled GM-CSF, according to an acute (12 weeks) followed by maintenance (6 months) schedule (1st level treated group). 2) PAP patients requiring the second WLL: a) the 1st level control group subjects will be randomized to receive WLL alone (2nd level control group) or WLL/GM-CSF (2nd level treated group); b) the 1st level treated group will receive WLL/GM-CSF (1st level re-treated group). 3) PAP patients requiring the 3rd WLL will receive WLL/GM-CSF (2nd level re-treated group). 4) PAP patients not requiring additional WLL, but with persistent lung abnormalities will receive the course of inhaled GM-CSF (Residual disease treated group). At scheduled time, the PAP patients will be evaluated by questionnaire, respiratory function testing, CT-assisted lung profusion score, severity score, quality of life form, clinical chemistry.~Expected results:~We plan to identify the best treatment schedule for PAP patients. We will be able to identify the optimal sequence of the treatments (i.e., WLL + short-term inhaled GM-CSF or WLL + short-and long-term inhaled GM-CSF) and the optimal treatment in case of recurrence.
The investigators designed an experimental, randomized by parallel groups, stratified according to previous treatment, open-label study evaluating the superiority of the combination of whole lung lavage/inhaled GM-CSF versus whole lung lavage alone in patients with pulmonary alveolar proteinosis. The primary efficacy objective is the total resolution of the pulmonary involvement. PAP patients matching the enrolment criteria will enter the study. If requiring the first WLL, they will be randomized to receive WLL (1st level control group) or WLL/followed by inhaled GM-CSF, according to an acute (12 weeks) followed by maintenance (6 months) schedule (1st level treated group).