Shanghai – November 06, 2026 -- China's Center for Drug Evaluation (CDE) accepted Lynk Pharmaceuticals' New Drug Application for zemprocitinib in moderate-to-severe active rheumatoid arthritis (RA) on November 4, moving the oral JAK1 inhibitor into regulatory review.
430-patient Phase III trial beat placebo at p<0.0001
The filing rests on a randomized, double-blind, placebo-controlled, multicenter Phase III trial in China. It enrolled 430 adults with moderate-to-severe active RA who had an inadequate response or intolerance to prior biologic disease-modifying antirheumatic drugs (bDMARDs). Zemprocitinib showed statistically significant efficacy over placebo on the primary and key secondary endpoints (p<0.0001). Lynk reports an overall favorable safety and tolerability profile.
Week 76 data show ACR70 responses rising to 62.4%
Among patients on continuous treatment through Week 76, ACR20 and ACR50 response rates held at 91.8% and 80.5%. The ACR70 response rate rose to 62.4%. The drug also sustained disease activity (DAS28-CRP ≤3.2) and physical function (HAQ-DI improvement ≥0.22) endpoints.
CEO Zhao-Kui (ZK) Wan said the data showed positive treatment effects in patients who had previously received JAK inhibitors, in addition to those with inadequate responses to bDMARDs. He called the acceptance "an important milestone for the company."
Lynk markets zemprocitinib as a highly selective second-generation JAK1 inhibitor
Lynk says the drug's greater JAK1 selectivity, compared with earlier-generation JAK inhibitors, could reduce safety risks from off-target effects while maintaining efficacy. Across completed or unblinded studies, rates of serious adverse events and adverse events of special interest were comparable to placebo, the company said.
Second China filing follows April atopic dermatitis acceptance
The CDE accepted a separate NDA for zemprocitinib in moderate-to-severe atopic dermatitis in April 2026. Lynk is also developing the compound for ankylosing spondylitis.
Lynk has a commercialization collaboration with Simcere covering rheumatology (RA, ankylosing spondylitis) and dermatology indications. Simcere Chief Medical Officer Dr. Aik Goh said treatment options are very limited for RA patients with an inadequate response to biologics, and that Simcere aims to bring the drug to patients as soon as possible.