Admilparant shows promise in idiopathic, progressive pulmonary fibrosis

The investigational oral lysophosphatidic acid receptor 1 antagonist admilparant helps delay disease progression in patients with idiopathic pulmonary fibrosis (IPF) or progressive pulmonary fibrosis (PPF), according to a phase II trial.

The study included 255 IPF patients aged ≥40 years (median age 69 years, 80 percent male) and 114 PPF patients aged ≥21 years (median age 71 years, 51.8 percent male) who had imaging evidence of >10 percent parenchymal fibrosis within the whole lung. These patients were randomly assigned to receive admilparant at 30 or 60 mg or placebo twice daily for 26 weeks. Background antifibrotics were permitted.

Disease progression, the main outcome, was defined as a composite of relative decline of ≥10 percent in percent predicted FVC (ppFVC), acute exacerbation, all-cause hospitalization, and all-cause mortality.

A total of 67.5 percent of patients with IPF and 36.8 percent of those with PPF were on background antifibrotics. The median time since diagnosis was 2.6 years in the IPF cohort and 2.9 years in the PPF cohort. In Median ppFVC at baseline was 77.3 percent and 64.7 percent in the IPF and PPF cohorts, respectively.

Over 26 weeks, time to disease progression was reduced with 60-mg admilparant vs placebo in both IPF (hazard ratio [HR], 0.54, 95 percent confidence interval [CI], 0.31–0.95) and PPF cohorts (HR, 0.41, 95 percent CI, 0.18–0.90). Results were consistent in the subgroup defined by baseline ppFVC (below or above the median value).

The most common first event in both IPF and PPF cohorts was a relative decline of ≥10 percent in ppFVC. No deaths were documented as first progression events.