Gyre Therapeutics Secures Conditional Approval Pathway for Hydronidone in China Following Successful Phase 3 Trial
核心洞察
Gyre Therapeutics completed a Pre-NDA meeting with China's CDE, achieving alignment on conditional approval pathway for Hydronidone based on existing Phase 3 clinical data.
The Phase 3 trial demonstrated that 52.85% of treated patients achieved ≥1-stage fibrosis regression at Week 52, compared with 29.84% in the placebo group (p=0.0002).
Hydronidone addresses a significant unmet medical need as there are currently no approved anti-fibrotic therapies for CHB-associated liver fibrosis patients.
Gyre Therapeutics has achieved a significant regulatory milestone in China, with its majority-owned subsidiary Gyre Pharmaceuticals (搜索) completing a successful Pre-New Drug Application meeting with the Center for Drug Evaluation (CDE) of China's National Medical Products Administration regarding Hydronidone, its first-in-class anti-fibrotic therapy for chronic hepatitis B-associated liver fibrosis.
Regulatory Alignment Achieved
During the meeting, Gyre Pharmaceuticals (搜索) and the CDE reached consensus that existing Phase 3 clinical data for Hydronidone are generally supportive of submission of a conditional approval NDA for the treatment of chronic hepatitis B (CHB)-associated liver fibrosis, including early (compensated) cirrhosis. The regulatory alignment was based on histologic improvement in liver fibrosis as measured by the Ishak fibrosis score.
The CDE further indicated that Hydronidone meets the criteria for inclusion in China's Priority Review and Approval Program for Innovative Drugs, subject to formal filing, acceptance and regulatory review. The NMPA previously granted Hydronidone Breakthrough Therapy Designation in March 2021, recognizing its potential to address a serious condition with significant unmet medical need.
Strong Phase 3 Clinical Results
The regulatory pathway is supported by robust Phase 3 trial results reported in May 2025, which demonstrated that Hydronidone met its primary endpoint. The trial showed that 52.85% of treated patients achieved ≥1-stage fibrosis regression at Week 52, compared with 29.84% in the placebo group (p=0.0002), based on centralized, blinded Ishak histologic assessment. The trial also achieved a key secondary endpoint evaluating improvement in liver inflammation without fibrosis progression and demonstrated a favorable safety profile consistent with prior clinical experience.
Mechanism of Action and Development Strategy
Hydronidone is a novel, orally administered anti-fibrotic agent designed to target key liver fibrosis pathways. It attenuates hepatic stellate cell activation and fibrogenesis by suppressing TGF-β1 (搜索)-induced signal transduction, including reduced p38γ phosphorylation and upregulated Smad7 (搜索) expression. This upregulation of Smad7 subsequently leads to downregulation of TGF-βRI (搜索) and inhibition of Smad2/3 (搜索) activation, thereby disrupting canonical TGF-β/Smad signaling and reducing fibrotic gene expression in hepatic stellate cells.
As part of the agreed regulatory pathway, the company plans to conduct an additional confirmatory clinical trial (referred to as a Phase 3c trial in China) designed to evaluate liver-related clinical outcomes to support potential conversion from conditional approval to regular approval. The company currently expects to submit an NDA for conditional approval of Hydronidone in the first half of 2026, subject to final data readiness and applicable regulatory procedures.
Addressing Significant Unmet Medical Need
"Hydronidone addresses a significant unmet medical need in patients with CHB-associated liver fibrosis, for whom there are currently no approved anti-fibrotic therapies," said Ping Zhang, Interim Chief Executive Officer of Gyre. "We are encouraged by the positive and constructive Pre-NDA dialogue with the CDE and the alignment achieved on a clear regulatory pathway. This milestone reflects the strength of our Phase 3 clinical data and supports our plans to advance Hydronidone toward conditional approval in China."
Market Opportunity in China
CHB-associated liver fibrosis represents a significant unmet medical need in China. According to China's national hepatitis B serological survey and internal epidemiological modeling, it is estimated that 60-70 million people in China are infected with hepatitis B virus, of whom approximately 14.7 million are diagnosed. Among these patients, an estimated 2.6 million have diagnosed, compensated, clinically significant liver fibrosis (F2-F4), excluding decompensated cirrhosis, and may be eligible for anti-fibrotic intervention.
Company Background and Pipeline
Gyre Pharmaceuticals (搜索) is a commercial-stage biopharmaceutical company committed to the research, development, manufacturing and commercialization of innovative drugs for organ fibrosis. Its flagship product, ETUARY® (pirfenidone capsule), was the first approved treatment for IPF in the PRC in 2011 and has maintained a prominent market share with 2024 net sales of $105.8 million. Hydronidone, a structural analogue of pirfenidone, represents the next generation of anti-fibrotic therapy in the company's pipeline.
Gyre Therapeutics, headquartered in San Diego, CA, is primarily focused on the development and commercialization of Hydronidone for liver fibrosis including MASH in the U.S. As of the third quarter of 2025, Gyre Therapeutics owns a 69.7% equity interest in Gyre Pharmaceuticals (搜索).