Premium
Adequate tacrolimus concentration for myasthenia gravis treatment
Author(s) -
Kanai T.,
Uzawa A.,
Kawaguchi N.,
Himuro K.,
Oda F.,
Ozawa Y.,
Kuwabara S.
Publication year - 2017
Publication title -
european journal of neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.881
H-Index - 124
eISSN - 1468-1331
pISSN - 1351-5101
DOI - 10.1111/ene.13189
Subject(s) - tacrolimus , medicine , myasthenia gravis , trough level , gastroenterology , prednisolone , urology , calcineurin , antibody titer , pharmacology , antibody , titer , transplantation , immunology
Background and purpose A single, oral dose of 3 mg/day tacrolimus, approved for myasthenia gravis ( MG ) treatment in Japan, was shown to reduce steroid dose and anti‐acetylcholine receptor ( AC hR) antibody titers as well as to improve MG symptoms. However, no studies have investigated the association between tacrolimus concentration and its clinical efficacy in MG . In this study, we aimed to determine the optimal tacrolimus concentration for MG treatment. Methods The trough tacrolimus concentration in 51 patients with MG (positive for anti‐ AC hR antibody, n = 48; negative for anti‐ AC hR and anti‐muscle‐specific tyrosine kinase antibodies, n = 3) who received 3 mg/day tacrolimus for more than 1 year was measured using a chemiluminescent enzyme immunoassay. The clinical characteristics of patients with MG as well as the dose of prednisolone used before and after tacrolimus treatment were evaluated retrospectively. Results The median trough tacrolimus concentration was 5.4 (range, 2.9–7.6) ng/mL, which was correlated with ‘minimal manifestation or better status’ ( P = 0.0190, r = 0.3273) and the reduction in anti‐ AC hR antibody 1 year after tacrolimus initiation ( P = 0.0170, r = 0.3465). When the cut‐off value for tacrolimus was defined as 4.8 ng/mL using a receiver operating characteristic curve, patients with adequate tacrolimus concentration (≥4.8 ng/mL) showed more reduction in anti‐ AC hR antibody titers and more improvement in MG‐related activities in daily life scores. More patients with adequate tacrolimus concentration achieved ‘minimal manifestation or better status’ compared with those with low tacrolimus concentration. Conclusions An adequate tacrolimus concentration is required for better MG prognosis.