Interstitial lung diseases with progressive pulmonary fibrosis: pathogenetic features and approaches to therapy

A number of patients with interstitial lung diseases (ILD) of various etiologies, including hypersensitive pneumonitis, diffuse connective tissue diseases (rheumatoid arthritis, systemic scleroderma, dermatomyositis), sarcoidosis, idiopathic non-specific interstitial pneumonia (NSIP) and unclassified ILD develop rapid deterioration of lung ventilation function due to the progression of fibrotic changes, accompanied by a decrease in physical performance and quality of life. It is proposed to distinguish a progressive fibrotic phenotype from those with similar pathogenetic mechanisms, radiologic pattern, clinical course, and prognosis. The progressive course of the fibrotic process is assessed by reducing the forced vital capacity of the lungs (FVC), increasing the severity of signs of pulmonary fibrosis according to computed tomography (CT) and worsening respiratory symptoms. There are several risk factors for the progression of ILD, such as male gender, older age, lower initial pulmonary function, and radiological or pathological picture of usual interstitial pneumonia (UIP). Currently, the role of antifibrotic drugs in the treatment of this pathology is being actively studied. Previously, the common approach was to use this group of drugs in patients with idiopathic pulmonary fibrosis (IPF) and immunosuppressive drugs in patients with other fibrotic subtypes of IL. However, the results of clinical studies have shown a favorable response to antifibrotic therapy for a wider range of fibrotic ILD, manifested in a decrease in the annual rate of FVC reduction. And in 2020, the use of the first anti-fibrotic drug was approved for the treatment of patients with advanced pulmonary fibrosis, NOT related to idiopathic pulmonary fibrosis (IPF)