Treatment of Graves' disease with the block-replace regimen of antithyroid drugs: the effect of treatment duration and immunogenetic susceptibility on relapse.

Antithyroid drugs are commonly used as first-line treatment for Graves' disease, but the optimum regimen for inducing remission remains unclear. We gave the block-replace regimen of carbimazole plus thyroxine to 100 patients for 6 or 12 months, to determine whether prolonged treatment is associated with fewer relapses. The remission rate one year after cessation of treatment was 59% with the 6 month course and 65% with 12 months; this was not significantly different. We also analysed HLA markers identified by restriction fragment length polymorphisms and could not confirm the recently reported associations of outcome with HLA-DR4 or with an HLA-DQA2 allele. These results show that six months treatment with a block-replace regimen of antithyroid drugs is probably sufficient, in the UK, to achieve maximum remission of Graves' disease and that there are no HLA markers which clearly predict outcome.

RCT Entities:   Population Interventions Outcomes