A Clinical Therapeutic Trial of Cyclosporine in Myasthenia Gravisa

Abstract

We randomly assigned 39 patients with steroid-dependent generalized myasthenia gravis to treatment with cyclosporine (5 mg/kg per body weight in divided doses) or placebo. Duration of treatment was 6 months. Patients were evaluated monthly. Primary measures of efficacy were quantified strength testing, antihuman acetylcholine receptor antibody titer, and dosage of corticosteroid medication. At the end of the study, patients in the cyclosporine group had significantly greater improvement in strength (p = 0.004) and a reduction in antireceptor antibody titer (p = 0.01). Percentage reduction of steroid medication was greater in the cyclosporine group, although the difference was not statistically significant (p = 0.12). There were no treatment failures, and there was one drug failure in the cyclosporine group. In the placebo group, there were three treatment failures. No significant nephrotoxicity was noted at this dosage during the first 6 months. During the subsequent 18 months of open-label therapy, continued reduction in steroid dosage occurred. Cumulative side effects, however, caused 35% of patients to discontinue the medication; 10% did so secondary to slowly progressive nephrotoxicity.

Myasthenia gravis: past, present, and future

“…Its efficacy in MG was first suggested by a small, randomized, placebo-controlled study, which has not been followed by similar studies on larger groups of patients (95). However, larger retrospective studies have supported its use as a steroid-sparing agent (96).…”

Performance of individual items of the quantitative myasthenia gravis score

“…It was first developed by Besinger in 1983 as an outcome measure for a clinical trial [1]. The scale was later modified by Tindal, and was used in a trial of cyclosporine in myasthenia gravis, where treated patients improved on average by 3.5 points compared to the placebo group [2,3]. Barohn in 1998 further modified the scale and performed an inter-observer reliability study [4].…”

Brazilian-Portuguese translation, cross-cultural adaptation and validation of the Myasthenia Gravis Composite scale. A multicentric study

“…The assessment instruments of HRQoL and clinical progression can be generic or specific to a particular group of diseases, such as MG 6 . Clinical trials to test new therapeutic interventions require some scale of clinical evaluation to assess the level of disease severity and the response to therapy 7,8 . Information about clinical evaluation and HRQoL, obtained through specific instruments, enable a better understanding of the patient's needs, and allow provision of adequate clinical support 6 .…”