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How long before Zilbrysq works?

Medically reviewed by Melisa Puckey, BPharm. Last updated on May 6, 2025.

Official answer

by Drugs.com

Zilbrysq starts working within the first week of treatment, with patients showing improvements in myasthenia gravis symptoms and a reduction of more than 2 points in the MG-ADL score. By the end of the 12-week Phase 3 RAISE trial, symptoms continued to improve with a 4.39 reduction of the daily functioning score.

While some individuals may notice symptom relief within the first week, others may require several weeks to experience significant improvements. Consistent daily administration is crucial to maintain its effectiveness.

Zilbrysq's effectiveness was measured using the Myasthenia Gravis–Activities of Daily Living (MG-ADL) score measures the severity of myasthenia gravis. The score is the result of 8 questions related to symptoms affecting talking, chewing, swallowing, vision, and the ability to perform functional activities related to daily living. The total score ranges from 0 (no symptoms) to 24 (severe symptoms). In clinical trials, the MG-ADL score is measured at the start of the trial and end of the trial.

References
  • Long-term safety and efficacy of zilucoplan in patients with generalized myasthenia gravis: interim analysis of the RAISE-XT open-label extension study [Accessed May 7, 2025]. https://pmc.ncbi.nlm.nih.gov/articles/PMC11025429/Zilbrysq Prescribing Information - FDA [Accessed May 7, 2025] https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/216834s008s009lbl.pdf

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