Tacrolimus monotherapy appears to be a safe and effective approach to drug-naïve myasthenia gravis (MG), according to study results published in Neuromuscular Disorders.
In this study, a total of 14 drug-naive patients with MG received tacrolimus alone, including 5 cases who had a subsequent thymectomy. Throughout the study, researchers allowed certain patients to use additional aggressive immunosuppressive therapies, including those without a thymectomy who had no minimal manifestation (MM) or better status after 3 weeks of tacrolimus, and those with thymectomy who had no MM or better occurred 1 to 2 weeks after surgery.
The mean age of patients at onset of the disease was 66.5 years and the mean duration of illness in patients before treatment with tacrolimus was started was 11 months. Approximately 57% (n = 8) of patients with generalized MG achieved MM or better status at the time of their initial assessment, while the remaining 43% (n = 6) of patients who did not meet this endpoint at that time did after 1 course of aggressive immunosuppressive treatment.
After 6 months, the study researchers observed significantly decreased MG values (P = 0.001), MG activities on daily life scales (P = 0.001), and antiacetylcholine receptor antibody levels with tacrolimus.
At the end of the follow-up period, which ranged from 41 to 70 months, all patients in this study achieved MM or better status. At the time of analysis, none of the patients had serious treatment-related side effects.
The limitations of this study included the single-center design, the lack of a control group, the small sample size, and the lack of a standardized protocol for selecting the aggressive therapies.
Based on their experience, the study’s researchers concluded that “tacrolimus monotherapy appears to be a safe and effective treatment for immunosuppressive drug-naïve patients as initial therapy [antiacetylcholine receptor] positive [ocular MG] or [generalized MG]. “However,” they added, “some MG patients with higher levels required additional fast-acting immunotherapies to achieve early MM or better status.”
Itani K., Nakamura M., Wate R. et al. Efficacy and safety of tacrolimus as long-term monotherapy in myasthenia gravis. Neuromuscular disorder. Published online on February 22, 2021. doi: 10.1016 / j.nmd.2021.02.010