Tacrolimus for myasthenia gravis: a clinical study of 212 patients.
Tacrolimus is a macrolide T cell immunomodulator that is used in myasthenia gravis (MG) patients to affect muscle contraction (ryanodine receptor by modulating intracellular calcium-release channels and increasing muscular strength), glucocorticoid receptors (increasing intracellular concentration of steroids and blocking the steroid export mechanism), and an increase in T cell apoptosis. In this study, we report the results of low-dose tacrolimus (0.1 mg/kg/day) treatment in 212 MG patients. There were 110 thymectomized, cyclosporine- and prednisone-dependent patients; 68 thymectomized patients who started tacrolimus early postoperatively (24 h after operation); and 34 patients over 60 years old with nonthymomatous generalized MG or in whom thymectomy was contraindicated. The mean follow-up time was 49.3 +/- 18.1 months. Muscular strength showed an increase of 23% after 1 month of treatment and 29% at the end of the study. The acetylcholine receptor antibodies decreased significantly from a mean of 33.5 nmol/L at base line to 7.8 nmol/L at the final visit. In the thymectomy group with combined prednisone and tacrolimus stratified by histology of the thymus, the mean probability to attain complete stable remission at 5 years was 80.8% in patients with hyperplasia, 48.1% in thymic involution, and 9.3% in patients with thymoma. In 4.9% of patients, tacrolimus was withdrawn because of major adverse effects. Our results suggest that a low dose of tacrolimus is effective for MG and could be included to the armamentarium for this autoimmune disease. The present results should be interpreted considering the limitations of a retrospective clinical study. Confirmation of these results in randomized studies is desirable.
Ponseti
José M
JM
Unit of Myasthenia Gravis, Department of Surgery, Hospital General Universitari Vall d'Hebron, Passeig Vall d'Hebron 119-129, E-08035 Barcelona, Spain. jmponseti@vhebron.net
Gamez
Josep
J
Azem
Jamal
J
López-Cano
Manuel
M
Vilallonga
Ramón
R
Armengol
Manuel
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D016559:Tacrolimus / Q000009:adverse effects / Q000627:therapeutic use*; D013934:Thymectomy
D007166:Immunosuppressive Agents; D016559:Tacrolimus