TUESDAY, Oct. 4, 2022 (HealthDay News) -- Pirfenidone may slow the rate of decline of forced vital capacity (FVC) among patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD), according to a study published online Sept. 5 in The Lancet Respiratory Medicine.
Joshua J. Solomon, M.D., from National Jewish Health in Denver, and colleagues conducted a randomized phase 2 trial at 34 academic centers specializing in ILD to examine the safety, tolerability, and efficacy of pirfenidone for RA-ILD. A total of 123 patients were randomly assigned to pirfenidone or placebo (63 and 60 patients, respectively). Due to slow recruitment and the pandemic, the trial was stopped early (March 31, 2020).
The researchers observed no significant difference between the groups in the proportion of patients who met the composite primary end point (decline in percent predicted FVC from baseline of 10 percent or more or death). Patients in the pirfenidone group had a slower rate of decline in lung function compared with the placebo group, measured by estimated annual change in absolute FVC and percent predicted FVC. The groups had similar decline in percent predicted FVC of 10 percent or more and frequency of progression.
"We were forced to terminate the trial due to unforeseen circumstances, including the abrupt consequences of the COVID-19 pandemic; as a result, the trial was underpowered to meet our primary end point," the authors write. "The totality of the evidence suggests that pirfenidone is effective in the treatment of RA-ILD."
Several authors disclosed financial ties to biopharmaceutical companies, including Genentech, which manufactures pirfenidone and funded the study.