Lynk Pharmaceuticals Reports Positive Phase III Results for Zemprocitinib in Rheumatoid Arthritis
核心洞察
Zemprocitinib, a selective JAK1 (搜索) inhibitor, met its primary endpoint with 79.1% of patients achieving ACR20 response at Week 24 versus 39.7% for placebo (P < 0.0001).
The Phase III trial enrolled 430 patients with moderate to severe rheumatoid arthritis (搜索) who had inadequate response to biologic DMARDs.
The drug demonstrated a favorable safety profile with most adverse events being mild to moderate in severity.
Lynk Pharmaceuticals (搜索) announced positive topline results from its Phase III clinical trial evaluating zemprocitinib (LNK01001) in patients with moderate to severe active rheumatoid arthritis (搜索). The study met its primary and key secondary efficacy endpoints, demonstrating statistically significant improvements versus placebo (P < 0.0001), with a favorable safety and tolerability profile.
Study Design and Population
The randomized, double-blind, placebo-controlled Phase III study (CTR20232969, NCT06276998) evaluated the efficacy and safety of zemprocitinib in patients with moderate to severe active rheumatoid arthritis (搜索) who had an inadequate response to biologic disease-modifying antirheumatic drugs (bDMARDs). The trial was led by Professor Xiaofeng Zeng from Peking Union Medical College Hospital and Chinese Academy of Medical Sciences.
The study enrolled 430 patients who were randomized 1:1 to receive zemprocitinib 12 mg twice daily or placebo twice daily. The primary endpoint was the proportion of patients achieving an ACR20 response at Week 24, with key secondary endpoints including the proportion of patients achieving ACR50 and DAS28 (CRP) ≤ 3.2 at Week 24.
Efficacy Results
The study demonstrated robust efficacy across all measured endpoints. ACR20 response rates at Week 12 and Week 24 versus placebo were 74.0% versus 29.9% (P < 0.0001) and 79.1% versus 39.7% (P < 0.0001), respectively. For the more stringent ACR50 endpoint, response rates at Week 12 and Week 24 versus placebo were 41.4% versus 9.3% (P < 0.0001) and 55.8% versus 22.0% (P < 0.0001), respectively.
The proportion of patients achieving DAS28 (CRP) ≤ 3.2 at Week 12 and Week 24 versus placebo were 51.2% versus 15.0% (P < 0.0001) and 67.0% versus 23.4% (P < 0.0001), respectively.
Safety Profile
Zemprocitinib was generally well tolerated throughout the study period. The majority of treatment emergent adverse events (TEAEs) were mild to moderate in severity (Grade 1–2). The incidence of serious adverse events was comparable between the zemprocitinib and placebo groups, and no new safety signals were observed. The overall safety profile was consistent with previous studies.
Clinical Significance
Professor Xiaofeng Zeng, the principal investigator, commented on the results: "Rheumatoid arthritis (搜索) is a chronic, progressive autoimmune disease that can severely impact patients' quality of life and physical health. In this Phase III study, zemprocitinib demonstrated strong efficacy, showing statistically significant improvements across the primary and key secondary efficacy endpoints, while maintaining a favorable safety and tolerability profile. These results suggest that zemprocitinib has the potential to offer a new treatment option for this patient population."
Dr. Zhao-Kui (ZK) Wan, Founder and Chief Executive Officer of Lynk Pharmaceuticals (搜索), noted: "This represents the first disclosed trial results in China for a selective JAK1 (搜索) inhibitor in patients with moderate to severe rheumatoid arthritis (搜索) who have had an inadequate response or intolerance to prior biologic therapies."
About Zemprocitinib
Zemprocitinib (LNK01001) is a highly selective, next generation JAK1 (搜索) inhibitor with best in class potential, being developed for the treatment of rheumatoid arthritis (搜索), ankylosing spondylitis, atopic dermatitis, and vitiligo. Compared with first-generation JAK inhibitors with lower selectivity, zemprocitinib exhibits significantly greater selectivity for JAK1, which may enhance efficacy while reducing off-target adverse effects.
The drug potently and dose-dependently inhibits multiple inflammation-related signaling pathways mediated by JAK1 (搜索). In March 2022, Lynk Pharmaceuticals (搜索) entered into a commercialization collaboration with Simcere (搜索) to jointly advance the development and commercialization of zemprocitinib for rheumatoid arthritis (搜索) and ankylosing spondylitis in Greater China.
The primary results of this study are planned to be formally presented at an upcoming international scientific conference.