Gyre Therapeutics recently announced its indirect, majority-owned subsidiary, Gyre Pharmaceuticals Co., Ltd. (Gyre Pharmaceuticals), has completed patient enrollment in the 52-week Phase 3 clinical trial of its Class 1 drug, Pirfenidone capsules, for the treatment of pneumoconiosis.

A total of 272 patients have been enrolled in this multicenter, randomized, double-blind, placebo-controlled trial being conducted at 18 clinical research centers across China. The trial is designed to evaluate the efficacy and safety of 52 weeks of Pirfenidone capsule treatment in patients with pneumoconiosis, a chronic occupational lung disease characterized by progressive pulmonary fibrosis.

Pneumoconiosis remains the most common and severe occupational disease in China, with more than 450,000 surviving patients and thousands of new cases reported each year. It results from long-term inhalation of mineral dusts such as silica or coal, which triggers persistent inflammation and progressive fibrosis of the lung tissue. Over time, this excessive scar formation causes diffuse fibrosis and irreversible loss of lung function. Despite its prevalence and severity, there is currently no approved therapy in China that specifically targets the fibrotic mechanisms underlying pneumoconiosis.

Based on recent expert consensus, China’s pneumoconiosis treatment landscape represents a significant unmet medical need, underscoring the importance of developing therapies specifically designed to slow or halt the progression of fibrosis and improve long-term outcomes for affected patients.

The ongoing trial compares Pirfenidone 1,800 mg/day (600 mg tid) with placebo over a 52-week double-blind treatment period.

• Primary Endpoint: Change from baseline in forced vital capacity (FVC) % predicted at Week 52.
• Key Secondary Endpoints: Changes in diffusing capacity of the lungs for carbon monoxide (DLCO), 6-minute walk distance, St. George’s Respiratory Questionnaire (SGRQ) score, and Modified Medical Research Council (mMRC) dyspnea scale, as well as rates of acute exacerbations, hospitalizations, and deaths.
• Safety Monitoring: Follows Gyre’s Development Safety Update Report (DSUR Dec 2023–Dec 2024). Most adverse events reported to date are mild to moderate, with no unexpected safety signals.
• Interim Analysis: None planned.

Pirfenidone is an oral antifibrotic small molecule that received its original approval in China in 2011 by Gyre Pharmaceuticals for the treatment of idiopathic pulmonary fibrosis (IPF). It works by inhibiting TGF-β signaling and fibroblast proliferation. Gyre continues to advance Pirfenidone beyond IPF through multiple clinical programs, including the Phase 3 pneumoconiosis trial and the recently approved Phase 2/3 trial for oncology-related pulmonary complications such as radiation-induced lung injury (RILI) and checkpoint inhibitor pneumonitis (CIP).

Gyre Therapeutics is a biopharmaceutical company headquartered in San Diego, CA, primarily focused on the development and commercialization of Hydronidone for liver fibrosis, including MASH, in the United States. Gyre’s strategy builds on its experience in mechanistic studies using MASH rodent models and clinical studies in CHB-induced liver fibrosis. In the People’s Republic of China, Gyre is advancing a broad pipeline through its indirect controlling interest in Gyre Pharmaceuticals, including therapeutic expansions of ETUARY®, and development programs for F573, F528, and F230.