OP0137 EFFICACY AND SAFETY OF TELITACICEPT, A NOVEL BLYS/APRIL DUAL INHIBITOR, IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: A PHASE 3, RANDOMIZED, PLACEBO-CONTROLLED 52-WEEK STUDY

Background Telitacicept (TACI-Fc fusion protein) is a novel BLyS (B-lymphocyte stimulator)/APRIL (a proliferation-inducing ligand) dual inhibitor, which has been approved in 2021 China for the treatment of patients with active systemic lupus erythematosus (SLE)[1]. Objectives Assess efficacy and safety telitacicept SLE double-blind, randomized, placebo-controlled, phase 3 trial. Methods In this study, 335 who were receiving stable standard therapy positive ANA/anti-dsDNA SELENA-SLEDAI score ≥8 randomized 1:1 to receive 160 mg (N=167) or placebo (N=168) subcutaneously weekly 52 weeks. The primary endpoint was response rate responder index 4 (SRI4) at Week 52. Key secondary endpoints included: SELENA-SLEDAI, PGA, immunological biomarkers including C3, C4, IgM, IgG, IgA CD19 + B cells. Safety assessed during study. Results Baseline demographics disease characteristics comparable between two groups. met, significantly greater proportion group vs achieving SRI4 (Table 1). sustained up (Figure 1A). Significantly proportions subjects had improvement PGA 1 & Figure 1B, 1C). Rapid increase C3 C4 1G, 1H), reduction cells 1D, 1E, 1F, 1I) observed following treatment. Incidences TEAEs infections Most mild moderate severity. A SAEs serious compared mg. 1. Response Rate (A), (B) (C) each visit. Percent (%) change from baseline IgM (D), IgG (E), (F), (G), (H) (I). # P<0.001 vs. Placebo; * P<0.01 P<0.05 Placebo. Table data. Efficacy, FAS Placebo Primary SRI-4 (MI), n(%) 64(38.1%) 138(82.6%) (NRI), 55(32.7%) 112(67.1%) (LOCF), 63(37.5%) Secondary $ ≥4-point SELENA SLEDAI 52, 68(40.5%) 117(70.1%) ≥0.3-point 94(56%) 141(84.4%) Severe SFI flare, Mean±SD 0.6±0.89 0.1±0.44 Safety, SS (N=168 ) (N=167 TEAE, 142(84.5%) 153(91.6%) SAE, 24(14.3%) 12(7.2%) Infections infestations (SOC), 101(60.1%) 109(65.3%) Upper respiratory tract infections, 71(42.5%) Urinary infection, 26(15.5%) 19(11.4%) Nasopharyngitis, 11(6.5%) 4(2.4%) Herpes zoster, 6(3.6%) 8(4.8%) Gastroenteritis, 5(3.0%) 9(5.4%) Serious 2(1.2%) p<0.001 Missing data imputed by multiple imputation. AEs an incidence ≥3% any listed. FAS, full analysis set. SRI, index. MI, missing NRI, as non-response. LOCF, last observation carry forward method. physician’s global assessment. SFI, flare SS, treatment-emergent adverse event. SOC, system organ class. Conclusion This trial met endpoint. showed good clinical benefits favorable profile patients. Reference [1]Dhillon S. Telitacicept: First Approval. Drugs. Sep;81(14):1671-1675. Acknowledgements their families participated Disclosure Interests Li Wang: None declared, JING LI: Dong Xu: Jianmin Fang Shareholder of: RemeGen Co., Ltd, Employee Ronald van Vollenhoven: Fengchun Zhang: declared.