Effects of low-dose methotrexate with MMI in patients with Graves' disease: results of a randomized clinical trial.

ABSTRACT

CONTEXT Supplemental methotrexate (MTX) may affect the clinical course of Graves' disease (GD). OBJECTIVE: Evaluate efficacy of add-on MTX on medical treatment in GD. DESIGN: Prospective, open-label, randomized supplementation controlled trial. SETTING: Academic endocrine outpatient clinic. PATIENTS One hundred and fifty-three untreated hyperthyroid patients with GD. INTERVENTION Patients received MTX 10 mg/d with methimazole (MMI) or MMI only. MTX and MMI were discontinued at months 12-18 in euthyroid patients. MAIN OUTCOME MEASURES: Discontinuation rate at months 18 in each group. RESULTS: In the MTX with MMI group, the discontinuation rate was higher than the MMI group at months 15-18 (50.0 vs. 33.3%, P=0.043, 95% CI 1.020 to 3.922; and 55.6 vs 38.9%, P=0.045, 95%CI 1.011 to 3.815, respectively). The decrease in TRAb levels in the MTX with MMI group was significant from baseline to months 6 compared to the MMI alone group [MTX+MMI 67.22% (43.12-80.32), MMI 54.85% (33.18-73.76), P= 0.039) and became more significant from months 9 [MTX+MMI 77.79% (62.27-88.18), MMI 69.55% (50.50-83.22), P= 0.035] to months 18 (P < 0.01 in 15-18 months). A statistically significant difference between the levels of TRAb in the MTX with MMI group and the MMI group at 9-18 months. There were no significant differences in the levels of FT3, FT4 and TSH between two groups. No serious drug-related adverse events were observed in both groups(P=0.771). CONCLUSIONS: Supplemental MTX with MMI resulted in higher discontinuation rate and improvement in decreased TRAb levels to homeostatic levels faster than methimazole treatment alone at months 12-18.