Pulmonary fibrosis can be associated with Anti-Neutrophil Cytoplasmic Antibody (ANCA) directed against MPO or with anti-MPO associated vasculitis, leading to increased disability and poor prognosis. The pathophysiology of this association remains unclear. Conventional therapies used for the treatment of vasculitis manifestations are often disappointing for the treatment of pulmonary fibrosis. The main cause of death in patients with anti-MPO ANCA associated vasculitis and associated pulmonary fibrosis is the progression of pulmonary fibrosis. No treatment has demonstrated efficacy to stabilize or improve pulmonary fibrosis associated with anti-MPO associated vasculitis.~Previous studies showed that Pirfenidone improves survival and pulmonary function in patients with idiopathic pulmonary fibrosis (IPF) and that Pirfenidone treatment is safe and well tolerated in IPF. Patients with anti-MPO associated vasculitis (or anti-MPO antibodies without vasculitis) and associated pulmonary fibrosis might benefit from the use of Pirfenidone. However, the efficacy and safety of pirfenidone in patients with anti-MPO associated vasculitis and associated pulmonary fibrosis has not been evaluated. This study was designed to assess the efficacy and safety of pirfenidone in patients with pulmonary fibrosis and anti-MPO ANCA associated vasculitis or anti-MPO antibodies without vasculitis.
The purpose of this study is to determine wether pirfenidone is safe and effective in the treatment of pulmonary fibrosis with anti-myeloperoxydase (MPO) antibodies or pulmonary fibrosis with anti-MPO associated vasculitis.