Pirfenidone for treating idiopathic pulmonary fibrosis: an evidence review group perspective of a NICE single technology appraisal

The National Institute for Health and Care Excellence (NICE) published guidance on the use of pirfenidone (Esbriet®, Roche) for the treatment of mild to moderate idiopathic pulmonary fibrosis (IPF) in 2013. NICE decided to review existing guidance following publication of an additional clinical trial, and invited the manufacturer of pirfenidone to submit evidence of its clinical and cost effectiveness for the treatment of mild to moderate IPF when compared with best supportive care (BSC) or nintedanib; nintedanib was a comparator only for moderate IPF. An independent Evidence Review Group (ERG) critiqued the company submission and this paper summarises their report and subsequent NICE guidance. The key clinical effectiveness evidence was based on three randomised controlled trials (RCTs) and an open-label extension study. Supportive data were provided from two additional RCTs conducted in Japan, while one additional open-label study was included for safety outcomes. Meta-analysis of the three key RCTs found pirfenidone to be effective at reducing disease progression compared with placebo, but statistically significant differences were not identified in all of the RCTs. A statistically significant reduction in all-cause mortality was only demonstrated when pooling data across studies. The treatment effects of pirfenidone and nintedanib were broadly similar, based on an indirect comparison using network meta-analysis, although they have slightly different adverse event profiles. There remains considerable uncertainty in the cost-effectiveness estimates for pirfenidone versus BSC, particularly due to uncertainty regarding the duration of treatment effect and the method used to implement the stopping rule within the economic model.