Idiopathic pulmonary fibrosis: an update.

Idiopathic pulmonary fibrosis (IPF) is the most common and lethal form of idiopathic interstitial pneumonia. The disease, which occurs primarily in middle-aged and older adults, is thought to arise following an aberrant reparative response to alveolar epithelial cell injury characterized by secretion of excessive amounts of extracellular matrix components, resulting in scarring of the lung, architectural distortion, and irreversible loss of function. A complex interplay between environmental and host factors is thought to contribute to the development of the disease, although the cause of IPF remains elusive and its pathogenesis incompletely understood. Over the last decade, disease definition and diagnostic criteria have evolved significantly, and this has facilitated the design of a number of high-quality clinical trials evaluating novel therapeutic agents for IPF. This massive effort of the medical and industry community has led to the identification of two compounds (pirfenidone and nintedanib) able to reduce functional decline and disease progression. These promising results notwithstanding, IPF remains a major cause of morbidity and mortality and a largely unmet medical need. A real cure for this devastating disease has yet to emerge and will likely consist of a combination of drugs targeting the plethora of pathways potentially involved in disease pathogenesis.