Promising Phase 2 Results for Efgartigimod alfa-fcab in Adults with Primary Sjögren’s Disease

Additionally, a median change in the Clinical European League Against Rheumatism Sjögren’s Syndrome Disease Activity Index (clinESSDAI) total score of -7 occurred in patients treated with efgartigimod alfa-fcab, compared with a total score of -4 in patients treated with placebo. The clinESSDAI is used to assess patients with primary Sjögren’s disease when evaluating disease activity independent of B-cell biomarkers or when biological data is not available. The total ClinESSDAI score is calculated by adding the scores from 11 organ-related domains—each with a potential score ranging from 0 to 3—and then weighting them with corresponding, domain-specific measures.

Secondary End Points

The cSTAR composite of five disease measures was a key secondary end point. In the study, patients treated with efgartigimod alfa-fcab had a 54.5% cSTAR response rate compared with a 33.3% response rate in patients treated with placebo. cSTAR is tool for assessing response in Sjögren’s disease used in clinical trials. It is a composite responder index that evaluates treatment effectiveness.

Additionally, patients treated with efgartigimod alfa-fcab had noticeable decreases in the disease-associated antibodies anti-Ro52 (-57% vs. +13%) and rheumatoid factor (-26.6% vs. -5.3%) compared with those who received placebo. Patients treated with efgartigimod alfa-fcab also had a greater decrease in C1Q immune complexes (-4.5 vs. -0.06 mc eq/mL) than those treated with placebo.

No new safety signals were identified.

Conclusion

This study served as proof of concept for using efgartigimod alfa-fcab for the treatment of patients with primary Sjögren’s disease.

A phase 3 trial, the UNITY trial (NCT06684847) is currently underway to assess the safety and efficacy of efgartigimod alfa-fcab in patients with primary Sjögren’s disease and a clinESSDAI score of 6 or greater, which indicates moderate to severe systemic disease activity.⁸

Michele B. Kaufman, PharmD, BCGP, is a freelance medical writer based in New York City and a pharmacist at New York Presbyterian Lower Manhattan Hospital.

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