Linkthera's Zemprocitinib Hits Primary Endpoint in Phase 3 COURAGE-RA in RA Patients with Inadequate bDMARD Response, Efficacy Maintained to Week 76

Zemprocitinib (LNK01001) is a highly selective, second-generation oral JAK1 inhibitor independently developed by Lynk Pharmaceuticals; its rheumatoid arthritis Phase III study is the COURAGE-RA study, registered as NCT06276998, planning to enroll 430 patients with moderate to severe active RA, with the primary endpoint of ACR20 response rate at Week 24, and the trial started on 2023-12-12 . The drug was developed by Lynk, with Simcere Pharmaceutical as its commercialization partner for the RA and ankylosing spondylitis indications in Greater China; Simcere also announced information on this Phase III trial in January 2026 . Prior to this long-term data release, the 24-week efficacy and safety data were set for presentation at EULAR 2026 (Abstract #OP0208) [Social media·G], and rheumatology media had already noted in the EULAR 2026 context that no new safety signal was seen for zemprocitinib in RA [Industry media·E].

This announcement covers the long-term results of the randomized, double-blind, placebo-controlled Phase III study: 430 patients with moderate to severe active RA who had inadequate response or intolerance to prior bDMARDs were randomized, and 429 received at least one dose; the primary and key secondary endpoints were met at Week 24 (p<0.0001). Among patients continuously treated with zemprocitinib 12 mg twice daily, ACR20, ACR50 and ACR70 response rates at Week 52 were 93.0%, 79.9% and 52.5%, and at Week 76 were 91.8%, 80.5% and 62.4%; the proportions achieving low disease activity of DAS28(CRP)≤3.2 at Weeks 52 and 76 were 85.5% and 81.4%, CDAI≤10 were 81.5% and 81.0%, and HAQ-DI improvement ≥0.22 were 84.5% and 86.7%. For patients initially on placebo who switched to zemprocitinib at Week 24, ACR20, ACR50 and ACR70 response rates at Week 76 were 92.0%, 77.6% and 55.1%. On safety, the profile during the 24-week double-blind period was comparable to placebo; up to Week 76 the safety profile remained consistent with no new safety signals, mean hemoglobin levels increased, Grade 3/4 ALT elevations and Grade 3 AST elevations were rare, and no Grade 4 AST elevation was reported.

Compared with previously disclosed information, this release extends the evidence from the 24-week double-blind period to 76-week long-term maintenance data; the key increment is confirming that ACR responses, low disease activity, and physical function improvements were sustained through 76 weeks of treatment, and that the placebo-switch group showed efficacy comparable to the continuous-treatment group. Principal investigator Professor Zeng Xiaofeng also noted that zemprocitinib showed good efficacy in patients with inadequate response to prior JAK inhibitor treatment, and Simcere's Chief Medical Officer Dr. Wu Yihan stated that the data provide further clinical evidence of its 'best-in-class potential'. These long-term data provide key support for its continued development in the bDMARD-refractory population.

Information not yet disclosed includes: detailed safety event incidence rates through Week 76, head-to-head or indirect comparisons with marketed JAK inhibitors, and the regulatory filing timeline and pathway for the RA indication, all to be confirmed. On subsequent milestones, the NDA for zemprocitinib in atopic dermatitis has been submitted to China's NMPA and accepted, the ankylosing spondylitis Phase III study is ongoing, and the RA registration filing progress warrants continued tracking.