Pliant Therapeutics Announces Positive Topline Data from a Phase 2a Collagen PET Imaging Clinical Trial of Bexotegrast in Patients with Idiopathic Pulmonary Fibrosis

12-week treatment with Bexotegrast 160 mg resulted in reduction of total lung collagen 
as measured by PET imaging, compared to an increase on placebo

Improvement in FVC and​ reduction in cough severity reported in bexotegrast-treated patients 
at all timepoints compared to placebo

Bexotegrast 160 mg was well tolerated over 12 weeks of treatment 
with no serious adverse events and no discontinuations

SOUTH SAN FRANCISCO, Calif., May 14, 2024 (GLOBE NEWSWIRE) -- Pliant Therapeutics, Inc. (Nasdaq: PLRX), today announced topline data from a 12-week, randomized, double-blind, placebo-controlled trial of bexotegrast (PLN-74809) conducted at Massachusetts General Hospital evaluating change in total collagen levels in the lungs of patients with idiopathic pulmonary fibrosis (IPF). IPF is a disease characterized by excessive collagen deposition in the lung.

Bexotegrast-treated patients showed reduced total lung collagen post treatment as measured by positron emission tomography (PET) imaging, compared to increased total lung collagen in the placebo group, suggesting potential reversal of fibrosis. Bexotegrast-treated patients demonstrated improvements in forced vital capacity (FVC) and reduction in cough severity across all timepoints compared to placebo. Bexotegrast 160 mg was well tolerated over 12 weeks with no drug-related serious adverse events (SAEs) and no discontinuations.

The trial evaluated bexotegrast at a once-daily dose of 160 mg versus placebo, and measured change in total lung collagen in 10 patients with IPF after 12 weeks of treatment. Patients underwent PET imaging with a collagen-binding radiotracer at baseline and Week 12.

The trial enrolled 7 patients in the active arm and 3 in the placebo arm. Eight out of 10 enrolled patients were on standard of care with the majority of those on nintedanib.

Bexotegrast 160 mg-Treated Patients Showed Reduced Total Lung Collagen Levels After 12 Weeks of Treatment, Suggesting Potential Reversal of Fibrosis

The primary endpoint of the trial was an evaluation of the change in standardized uptake value (SUV) of ⁶⁸GA-CBP8, a PET ligand that binds to type 1 collagen. Type 1 collagen is the predominant collagen type produced in the lungs as a result of IPF.¹ An increase in SUV of in the lung indicates increased total lung collagen and potential progression of disease. IPF patients have been shown to exhibit higher SUV values compared to healthy subjects.² Additionally, patients with increased total lung collagen as measured by PET imaging had an increased risk of death.³