NEW research has shown that induction cyclophosphamide with maintenance immunosuppression is a safe and effective treatment for high-risk myasthenia gravis (MG), offering rapid remission and long-term benefits in carefully selected patients.
This retrospective cohort study evaluated the long-term safety and efficacy of cyclophosphamide in managing refractory or high-risk MG, a condition often resistant to conventional immunosuppressive therapies. Conducted at a quaternary neuroimmunology clinic in New South Wales, Australia, the study aimed to address the unmet need for sustainable remission in this patient population while minimising reliance on toxic or burdensome therapies such as corticosteroids, plasma exchange, or intravenous immunoglobulin.
The analysis included 31 patients treated with an induction cyclophosphamide protocol from January 2000 to June 2022, with a median follow-up of 3.6 years (range: 5 months to 11 years). Patients had a mean age of 64 years, 94% were seropositive for acetylcholine receptor (AChR) antibodies, and 45% had thymoma. After the third cycle of cyclophosphamide, median myasthenia gravis composite scores reduced by over 50%. Eleven patients achieved complete cessation of prednisolone, while 20 reduced their median daily dose to 5 mg. Notably, 62% of patients were able to discontinue plasma exchange, and 55% ceased intravenous immunoglobulin. Cyclophosphamide was well-tolerated, with only mild cytopenias observed; there were no cases of malignancy or haemorrhagic cystitis.
These findings highlight the potential role of induction cyclophosphamide in rapidly achieving remission, reducing corticosteroid dependence, and minimising the need for repeated injectable therapies. For high-risk MG patients, especially those with AChR antibodies, this approach offers an effective and safe alternative to traditional immunosuppressive regimens. Clinicians should consider integrating this protocol into practice for selected patients, balancing its efficacy with appropriate safety monitoring. Future research should explore prospective studies and the optimisation of maintenance regimens to further enhance patient outcomes.
Katrina Thornber, EMJ
Reference
Chan F et al. Induction cyclophosphamide with maintenance immunosuppression in high-risk myasthenia gravis: long-term follow-up and safety profile. Journal of Neurology, Neurosurgery & Psychiatry. 2024;95:1096-101.
