The Effectiveness of an Empirical Chinese Medicine Formulation for Idiopathic Pulmonary Fibrosis: an Open Label Clinical Trial

Background Idiopathic pulmonary fibrosis (IPF) is a dreadful disease characterized by progressive impairment in quality of life, increasingly limited physical function, and an early death from respiratory failure. IPF is the most common and predominantly lethal form of the idiopathic interstitial pneumonias, with an associated median survival of only 2 to 3 years. The etiology of this chronic and progressive fibrotic lung disease is unknown, although potential risk factors such as cigarette smoking and other environmental exposures have been described. In a study published in 2006 based on a United States healthcare claims database, the prevalence of IPF was between 14-42.7 per 100,000, depending on whether narrow or broad case-finding criteria was used. IPF is more commonly seen in patients between 40 to 70 years of age. The risk of death as a result of IPF also increases with age, with a hazard ratio of 0.25 for patients younger than 50 years and a longer median survival amongst those younger than 50 (116.4 months compared to 62.8 months). IPF occurs more commonly in men than in women and also progress faster and result in worse survival in men. The IPF mortality rate in the United States was found to be 61.2 deaths per 1,000,000 in men and 54.5 per 1,000,000 in women, nevertheless, the death rate in women is increasing at a faster rate than in men. Age-adjusted mortality has been found to be greater among whites than blacks and is increasing at a higher rate among whites when compared to other racial and ethnic groups. There is no effective treatment for IPF, although pirfenidone and nintedanib have been approved for treatment of IPF, with benefit in slowing down lung function decline. At present, the only intervention that improves survival in select patients with IPF is lung transplantation. With this to look forward to, it is no surprise that patients and their physicians are desperate for treatment options that might change the outcome. Traditional Chinese herbal medicine has been an important source to treat this ailment.

Traditional Chinese medicine (TCM) has dealt with IPF for long time. A condition similar to pulmonary fibrosis can be found in Chinese literature thousands years ago. A disease termed "Fei Wei" was described and is similar to IPF in definition, pathophysiology, and treatment. It was reported that the disease was extremely difficult to treat. Other TCM terms of respiratory disease similar to IPF were "short breath", "cough", "lung inflation", and "Fei Bi".

In recent years, TCM has renewed its focus on pulmonary fibrosis and other respiratory illnesses because of SARS (Severe Acute Respiratory Syndrome), a viral infection which spread in China in late 2002 and 2003. SARS infection resulted in pulmonary fibrosis in a number of individuals who contracted SARS, although the pathophysiology of pulmonary fibrosis resulting from SARS may differ from that of IPF, the fibrosis can be reversible. In TCM, the pathophysiology for IPF is a complex of group of terms: Feng (Wind-external factor), Re (Heat-inflammation), Tan (Phlegm), Yu (Congestion). Treatment may vary according to the phases of the disease, symptoms, and individuals.

IPF causes pulmonary interstitial chronic inflammation, immune complex deposition in the lung interstitium into fibroblasts and collagen eventually leads to the destruction of lung tissue. In TCM terms, this represents Blockage of Heat in the lung. With Heat in the pulmonary mass, the Lung loses the function of controlling Qi, hence the patients suffers difficulty in breathing, has no air suction, has shortness of breath, dry cough, wheezing, and other symptoms.

In China, herbal medicine is the main treatment for IPF. Research has shown the effectiveness of traditional Chinese herbs formulations developed to treat IPF. The Individual herbs of the formula have been widely used to improve pulmonary function.