Interstitial lung disease (IDL) is actually a group of many diseases that slowly cause inflammation and scarring in the lungs. This scarring is termed pulmonary fibrosis.
Idiopathic pulmonary fibrosis (IPF) is the largest of the interstitial lung diseases. IPF happens over the time span of several years. As the lungs become fibrotic, they lose their ability to function and transfer oxygen into the blood. The result is that the vital organs in the body do not receive enough oxygen and they in turn lose their ability to function. While a small number of patients with fibrosis of the lungs have an autoimmune disease and another small group have hereditary or “familial” pulmonary fibrosis, in most cases there is no obvious cause.
IPF is not easily diagnosed. Patients can have dyspnea and/or a nonproductive cough for months. Other symptoms such as chest pain, loss of appetite, weight loss, fatigue, weakness and shortness of breath during activity can begin 1-2 years before diagnosis. Confirmation of the diagnosis requires integrating clinical, laboratory, radiologic, and/or pathologic data. Chest X-rays show diffuse reticular opacities, but are non-specific. High-resolution computed tomography (HRCT) is significantly more sensitive and specific as a diagnostic tool. As IPF progresses, a HRCT scan takes on the appearance resembling a honeycomb. Pulmonary function tests can often be useful as a diagnostic tool.
IPF has no cure. Many people live only 3 to 5 years after diagnosis. The most common cause of death related to IPF is respiratory failure. Other causes include pulmonary hypertension, heart failure, pulmonary embolism and pneumonia.
Reports of the incidence and prevalence of IPF in both the US and Europe vary greatly depending on the definition. Representatives from United BioSource, Boehringer Ingelheim and Genzyme performed a comprehensive review of English language literature published between January 1990 and August 2011. They Identified and summarized 15 studies. The results show a prevalence range of 134,000 – 198,000 and an incidence range of 21,000-28,000 for the broader definition of the disease in the US. In Europe, prevalence is estimated at up to 173,000.
According to the International Society for Heart and Lung Transplantation, from January, 2011 through the end of June, 2012, IPF was the number one reason for a lung transplant in their registry. There were almost 1,000 lung transplants worldwide for IPF.
InterMune’s Esbriet (pirfenidone) was approved in the USA in October 2014. It had previously been approved for marketing in 29 European countries, Mexico and Canada. Intermune is now part of Genentech (Roche). Pirfenidone is an orally active, small molecule drug that works by inhibiting TGFβand TNF-α synthesis.
On the same day, the FDA also approved another IPF drug, Ofev, from Boehringer Ingelheim. Both drugs will offer new hope for patients, but possibly a problem for insurance companies and the government because of their high prices.
Roche said the wholesale price of Esbriet would be about $7,800 a month, or $94,000 a year. This is two to three times higher what the drug sells for in Canada and Europe. Boehringer Engelheim priced its new treatment at $96,000 a year, slightly higher than Roche.
In Europe After some pushback the UK’s cost containment agency, National Institute of Health and Clinical Excellence (NICE), decided to allow reimbursement for Esbriet. The price is approximately $39,350 per patient per year. Pricing in top15 EU countries is $33K–47K per patient per year.