The monoclonal antibody pamrevlumab does not appear to improve outcomes for patients with idiopathic pulmonary fibrosis when compared with placebo, according to the phase III ZEPHYRUS-1 trial.
ZEPHYRUS-1 included 356 idiopathic pulmonary fibrosis patients (mean age 70.5 years, 72.5 percent male, 62.1 percent White) who were not receiving antifibrotic treatment with nintedanib or pirfenidone at enrolment. These patients were randomly assigned to receive treatment with either pamrevlumab 30 mg/kg (n=181) or placebo (n=75), administered intravenously every 3 weeks for 48 weeks.
Absolute change in forced vital capacity (FVC) from baseline to week 48 was the primary endpoint. Time to disease progression (decline of ≥10 percent in predicted FVC or death) and adverse events, among others, were also assessed.
A total of 277 patients (77.8 percent) completed the trial. Absolute change in FVC from baseline to week 48 did not significantly differ between the pamrevlumab and placebo arms (least-squares mean, −260 vs −330 mL; mean difference, 70 mL, 95 percent confidence interval [CI], −60 to 190; p=0.29).
Likewise, no significant between-group differences were observed in any of the secondary outcomes or in the patient-reported outcomes.
As for safety, treatment-related adverse events occurred in 88.4 percent of patients in the pamrevlumab arm and in 86.3 percent in the placebo arm. Serious adverse events were reported in 28.2 percent and 34.3 percent of patients, respectively. Death rates were 12.7 percent with pamrevlumab and 13.1 percent with placebo.