R&D(research and development)

Interstitial Lung Disease

Interstitial lung disease includes many different lung conditions which affect the lung function through over-production and deposit of collagen in the interstitium of lung to make it thicker. The interstitium is a lace-like network of tissue that provides support to the lungs' alveoli. Small blood vessels travel through the interstitium to allowing gas exchange between blood and the air. The causes of ILD can be inflammation, scarring, or extra fluid (edema).

There are many types of ILD. The most common ones are:

Interstitial pneumonia caused by bacteria, viruses, or fungi infection; Idiopathic pulmonary fibrosis (IPF) with unknown etiology; Nonspecific interstitial pneumonitis (NSIP) associated with autoimmune conditions such as rheumatoid arthritis (RA) or scleroderma (SD). Sometimes, it is also categorized as connective tissue disease associated interstitial lung disease or CTD-ILD. Hypersensitivity pneumonitis caused by pollution Drug-/Radiation-induced ILD, such as radiation pneumonitis (RP) relatively common following radiotherapy for chest wall or intrathoracic cancer.

Shortness of breath is the most common symptom of ILD. Cough is another major symptom of ILD patients. The shortness of breath may take years to develop. In acute interstitial pneumonitis such as RP, symptoms come on more rapidly in weeks. So far high-resolution CT scan is still the best method to diagnose ILD.

The intra-cellular mechanism leading to over-production and deposit of collagen is still unclear, although TGF-beta, VGF, PDGF, and FGF signaling pathways are implicated in the disease process.

Before pirfenidone (Etuary®) is approved by FDAs of China, US, EU, and Japan for IPF treatment, steroid was the only treatment with serious side effect and questionable efficacy. Currently, Etuary® is under development for additional indications of other ILD such as RP and CTD-ILD.