Miyastenia Gravis’in Serolojik Alttiplerinde Rituksimabın Uzun Dönem Klinik Sonuçları

Öz

Rituksimab, B hücrelerini tüketen bir monoklonal antikor olarak, özellikle tedaviye dirençli olgularda miyastenia gravis (MG) tedavisinde giderek artan bir ilgi görmektedir. Ancak, farklı serolojik alt tiplerdeki uzun dönem etkinliği hâlen araştırılmaktadır. Bu çalışma, anti–asetilkolin reseptörü (AChR) antikorları, anti–kas-spesifik kinaz (MuSK) antikorları ve çift seronegatif profilleri içeren jeneralize miyastenia gravis (MG) hastalarında rituksimab tedavisinin uzun dönem klinik sonuçlarını değerlendirmeyi amaçlamıştır. 2012–2024 yılları arasında Nöromüsküler Ünitede retrospektif, kesitsel bir çalışma yürütülmüştür. Rituksimab tedavisi alan ve en az 12 aylık takip süresi bulunan 36 hasta çalışmaya dahil edilmiştir. Tedavi sonuçları, başlangıçta, 6. ayda ve son değerlendirmede MGFA ve MGFA-PIS skorları kullanılarak değerlendirilmiştir. Antikor durumuna göre alt grup analizleri yapılmıştır. Tüm serolojik alt gruplarda kalıcı klinik iyileşme gözlenmiştir. Altıncı ayda hastaların %70’i MGFA-PIS’e göre iyileşme veya remisyon göstermiş olup, bu oran son değerlendirmede %100’e yükselmiştir. AChR+ ve MuSK+ hastalar erken ve kalıcı yanıt gösterirken, çift seronegatif hastalarda gecikmiş ancak anlamlı bir fayda saptanmıştır. Rituksimab, tüm ana antikor alt tiplerinde yarar sağlayan, jeneralize MG için güvenli ve etkili bir uzun dönem tedavi seçeneği olarak görünmektedir. AChR+ ve MuSK+ hastalarda 6. ay ile son takip arasındaki farkın anlamlı olmaması, erken dönemde elde edilen iyileşmenin uzun dönemde de sürdüğünü göstermektedir.

Anahtar Kelimeler

• Miyastenia Gravis
• rituksimab
• anti–asetilkolin reseptörü antikoru
• anti–kas-spesifik kinaz antikoru
• seronegatif

Long-Term Clinical Outcomes of Rituximab Across Serological Subtypes of Myasthenia Gravis

Öz

Rituximab, a B-cell-depleting monoclonal antibody, has gained increasing attention as a therapeutic option for myasthenia gravis (MG), particularly in refractory cases. However, its long-term efficacy across different serological subtypes remains to be investigated. This study aimed to evaluate the long-term clinical outcomes of rituximab treatment in patients with generalized myasthenia gravis (MG), including those with anti-acetylcholine receptor (AChR) antibodies, anti-muscle-specific kinase (MuSK) antibodies, and double-seronegative profiles. A retrospective cross-sectional study was conducted at the Neuromuscular Unit between 2012 and 2024. Thirty-six patients who received rituximab and had a minimum follow-up of 12 months were included. Treatment outcomes were assessed using MGFA and MGFA-PIS scores at baseline, at 6 months, and at the final evaluation. Subgroup analyses were performed based on antibody status. Sustained clinical improvement was observed in all serological subgroups. At six months, 70% of patients showed improvement or remission according to MGFA-PIS, increasing to 100% at final evaluation. AChR+ and MuSK+ patients demonstrated early and persistent responses, while a delayed but significant benefit was seen in double-seronegative patients. Rituximab appears to be a safe and effective long-term treatment for generalized MG, with benefits observed across all major antibody subtypes. The lack of a significant difference between the 6-month and final follow-up in AChR+ and MuSK+ patients suggests that the early improvement was sustained in the long term.

Anahtar Kelimeler

• Myasthenia Gravis
• rituximab
• anti-acetylcholine receptor antibody
• anti-muscle-specific kinase antibody
• seronegative

Kaynakça

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