Pliant Therapeutics' Drug Trial Shows Promise In Reversing Lung Fibrosis In Patients

On Tuesday, Pliant Therapeutics Inc PLRX announced topline data from a Phase 2a PET Imaging trial of bexotegrast (PLN-74809) evaluating change in total collagen levels in the lungs of patients with idiopathic pulmonary fibrosis (IPF) 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. 

After 12 weeks of treatment, bexotegrast-treated patients showed a reduction in standardized uptake value (SUV) of 68GA-CBP8 in the lung compared to an increase in placebo. 

68GA-CBP8 is a PET ligand that binds to type 1 collagen.

This reduction in SUV indicates reduced total lung collagen in the treated group, suggesting a potential reversal of fibrosis.

Bexotegrast-treated patients demonstrated improvements in forced vital capacity (FVC) and reduced cough severity compared to placebo. 

The trial’s exploratory efficacy endpoints assessed changes in FVC forced vital capacity percent predicted (FVCpp), patient-reported cough severity, and fibrosis biomarkers. 

Bexotegrast-treated patients experienced improved lung function, as measured by FVC and FVCpp, with a clear separation from placebo.

Across all time points, bexotegrast-treated patients experienced reduced patient-reported cough severity compared to placebo patients.

At weeks 4 and 12, bexotegrast-treated patients demonstrated a reduction in circulating biomarkers integrin beta-6 and PRO-C3 relative to placebo.

PRO-C3, a serum biomarker of type III collagen synthesis, is elevated in patients with IPF and associated with progressive disease.

Bexotegrast was well tolerated at 160 mg over 12 weeks of treatment, with no serious adverse events reported. 

Most frequently reported treatment-emergent adverse events were mild in severity with no trial discontinuations.

Price Action: PLRX shares are up 1.3% at $13.90 at last check Tuesday.

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