The study, “Pirfenidone improves survival in IPF: results from a real-life study,” was published in the journal BMC Pulmonary Medicine.
Genentech’s Esbriet is an approved IPF treatment that slows the decline in lung function. Results from Phase 3 trials, namely the ASCEND (NCT01366209) and CAPACITY (NCT00287716 and NCT00287729) trials, showed that treatment with Esbriet significantly reduced IPF disease progression. In particular, the therapy reduced IPF patients’ decline in lung function and physical capacity, the number of respiratory-related hospitalizations, and the risk of death, compared with a placebo.
In fact, a 2014 study reported that Esbriet could reduce the risk of death at one year by 48 percent in IPF patients enrolled in the ASCEND trial.
To further study the impact of Esbriet on patient survival outside the restrictions of a clinical trial, researchers performed a retrospective analysis of a group of 82 IPF patients enrolled in an outpatient clinic at the University Hospital of Heraklion (UHH) in Greece.
According to the team, this type of real-world study in which “patients with advanced disease and comorbidities are included, are needed to shed light to the mortality benefit of pirfenidone in the general IPF population.”
All 82 patients analyzed had not had any previous treatment before the study and had completed at least three months of treatment with Esbriet (2403 mg/day) by the time of the analysis. Their mean age was 74.9 years, and they were followed for up to three years.
Lung function tests, such as spirometry and diffusing capacity of the lung for carbon monoxide (DLCO; the ability of the lungs to transfer oxygen from inhaled air to the blood), were performed at the time of IPF diagnosis, and thereafter at three, six, 12, 24, and 36 months from the start of Esbriet treatment.
In total, 15 patients died during the study period. The three-year survival rate of patients was 73 percent.
To better understand the effects of Esbriet on survival rates, researchers compared the data from their UHH group to a group of IPF patients followed at the Royal Brompton Hospital (RBH) in the United Kingdom who had not received anti-fibrotic treatment.
“Nowadays, it is not ethical to withhold pirfenidone therapy to establish a true control group, and therefore we chose to use a historical cohort as a control group,” the researchers wrote.
This final analysis included 136 patients from the RBH group and 75 patients from the UHH group.
After the exclusion of severe cases (those with a DLCO below 30 percent), results showed that the survival rate was higher in the UHH group than in the RBH group. This difference in survival rate remained even after adjusting for age, gender, and forced vital capacity, a measure of lung function.
An age-matched model comparing survival between the two groups showed that the mortality rate was reduced in the UHH group, with a hazard ratio of 0.30, meaning a 30% reduction compared with the RBH group.
Researchers detected no new safety issues with Esbriet treatment; all events reported were in line with the known safety profile of the therapy. Of note, 30 patients reported gastrointestinal discomfort, and 17 patients experienced photosensitivity.
These results showed an “increased 3 years survival rate in patients treated with pirfenidone, and a survival benefit of 30% compared to patients treated with no antifibrotic agents,” the researchers wrote.
“The effect of pirfenidone on survival is remarkable if ones takes into account that patients with comorbidities and severe disease have been included in the UHH cohort unlike what happens in pharmaceutical trials,” they added.