argenx Presents New Efgartigimod Data at EULAR 2025 Highlighting Positive Phase 2 Proof-of-Concept Results in Myositis and Sjogren’s Disease

Core Insights - Argenx SE announced positive results from Phase 2 studies of VYVGART® (efgartigimod) for treating Sjogren's disease and idiopathic inflammatory myopathies, presented at EULAR 2025 [1][2][3] - The FDA granted efgartigimod Fast Track designation for primary Sjogren's disease treatment, indicating its potential for expedited development [2] Group 1: Efgartigimod in Myositis - The ALKIVIA Phase 2/3 study showed significant improvement in muscle strength and physical function in myositis patients treated with efgartigimod, with a mean Total Improvement Score (TIS) of 50.45 compared to 35.65 in the placebo group (P=0.0004) [4][5] - 79% of efgartigimod-treated patients achieved moderate improvement (TIS ≥40), while only 47% of placebo patients did [4] - Efgartigimod demonstrated a favorable safety profile, with similar rates of treatment-emergent adverse events between efgartigimod and placebo groups [5][11] Group 2: Efgartigimod in Sjogren's Disease - In the Phase 2 RHO study, 45.5% of efgartigimod-treated patients showed improved outcomes on the CRESS composite primary endpoint at Week 24, compared to 11.1% in the placebo group [9][10] - The median change in clinESSDAI total score was -7.0 for efgartigimod patients versus -4.0 for placebo [9] - Efgartigimod led to a ~60% reduction in IgG levels from Week 4 onwards, indicating its potential for disease biology modulation [10][12] Group 3: Ongoing Studies and Future Directions - The Phase 3 portion of the ALKIVIA study is ongoing to further evaluate efgartigimod's efficacy in myositis [6] - The Phase 3 UNITY trial is assessing efgartigimod's efficacy and safety in moderate to severe Sjogren's disease [11] - Argenx is committed to exploring new therapeutic areas in rheumatology, with ongoing studies in both myositis and Sjogren's disease [8][20]