[Therapeutic efficacy and safety of tacrolimus for intractable myasthenia gravis: a report of 36 patients].

OBJECTIVE

To examine the efficacies and adverse events of low-dose tacrolimus in intractable myasthenia gravis (MG) patients during a long-term follow-up.

METHODS

Tacrolimus was administered at 0.1 mg×kg(-1)×d(-1) to 36 generalized or ocular MG patients at our department from November 2008 to December 2010. The efficacies of tacrolimus were assessed by the myasthenia gravis activities of daily living (MG-ADL) profile and the classification of Myasthenia Gravis Foundation of America (MGFA). And the adverse events of tacrolimus were monitored in each patient.

RESULTS

(1) All patients were followed up for 7 - 23 months. Adverse events occurred in 6 patients (16.67%). (2) The myasthenic symptoms improved up to the levels of MG-ADL and MGFA in 24 patients (66.67%). There was notable statistical significance in the comparison of clinical status at pre- and post-treatment (P = 0.000). (3) The efficacies in patients with generalized MG were better than those with ocular MG (P = 0.032). (4) The average blood trough levels of tacrolimus were lower than the recommended maintenance range from other countries in 24 effective patients.

CONCLUSION

The administration of tacrolimus induces symptomatic improvements in MG patients especially in generalized type. And the adverse events should be closely monitored.