Two-year treatment with cyclosporine microemulsion for responder myasthenia gravis patients

Cyclosporine (CsA) microemulsion pre-concentrate (MEPC) is a potential steroid-sparing agent for myasthenia gravis (MG) patients; however, there is a paucity of information on the long-term use of CsA MEPC in these patients.

We examined the efficacy and safety of CsA MEPC therapy administered to MG patients in a 2-year prospective open trial.

From Hanamaki General Hospital and Keio University Hospital, 28 patients provided informed consent. They were enrolled in a prospective open study of CsA MEPC for the initial 6-month observation period; after this 9 were defined as poor responders and excluded from the long-term analysis.

The proportion of patients with minimal manifestations or pharmacologic remission status increased significantly. Among 18 patients taking oral prednisolone, 16 (88.9%) achieved a >or=50% reduction in prednisolone dose. Time to attain the minimal quantitative MG (QMG) score (4.2 +/- 2.6) was 4.2 +/- 4.2 months. Time to attain the minimal dose of prednisolone (2.9 +/- 3.1 mg/day) was 9.3 +/- 6.9 months. The dose of CsA MEPC was reduced to 2.6 mg/kg/day 2 years after starting the drug. Both total and ocular QMG scores were significantly decreased at 6 months and were generally maintained thereafter. The dose of prednisolone was significantly reduced at 1 year, and further reduced at 2 years. BMI decreased significantly, and 9 of 12 (75%) patients complaining of moon face reported that this had resolved on exit. All patients tolerated CsA MEPC without significant side effects.

CsA MEPC therapy in responder MG patients suppressed disease severity, reduced steroid requirements, and alleviated steroid-related side effects. These findings should be confirmed by prospective controlled double-blind trials.