Clinical evaluation of efficacy of leflunomide combined with low-dose prednisone for treatment of myasthenia gravis.

This study evaluated the clinical efficacy of leflunomide combined with low-dose prednisone (0.25 mg/kg/day) for treatment of myasthenia gravis (MG). We enrolled 32 MG patients treated with leflunomide combined with low-dose prednisone. In the control group, 14 patients were treated with low-dose prednisone. Improvement in MG composite (MGC) score of ≥ 3 points from enrollment to 12-week follow-up indicated that the treatment was effective. In the leflunomide combined low-dose prednisone group, the median of MGC score at the time of enrollment was 8.5 points. After 12 weeks, the MGC score dropped to four points. There was statistically significant difference in MGC score before and after treatment (p < 0.001). In the low-dose prednisone group also followed up for 12 weeks, the median of MGC score of the patients decreased from 7 to 4 points, and the change was not statistically significant (p = 0.05). In the leflunomide combined low-dose prednisone group, the improvement of clinical symptoms occurred mainly in the first 4 weeks and the last 4 weeks. Relatively, the decline of the score was mostly seen during the first 8 weeks in the low-dose prednisone group. In leflunomide combined with low-dose prednisone group, the effective rate of generalized MG(gMG) was significantly higher than ocular MG(oMG) (χ2 test, p = 0.036). However, there is no significant difference in the effective rate between AChR-Ab-positive and -negative groups (Fisher's Exact Test, p = 0.625). No serious side effects were observed in any of the subjects. Leflunomide combined with low-dose prednisone rapidly improved the clinical symptoms of patients with MG. It may be a promising treatment for gMG.