説明
Methotrexate is intentionally combined with adalimumab in rheumatoid arthritis and other autoimmune conditions to reduce adalimumab immunogenicity and improve efficacy; co-administration requires monitoring for additive immunosuppression.
機序
Methotrexate reduces the formation of anti-drug antibodies (ADA) against adalimumab, increasing its serum trough concentrations and response rates; the combination produces additive immunosuppression through different mechanisms (TNF-alpha blockade vs. folate metabolism inhibition).
臨床的意義
PREMIER and ARMADA trials confirm improved clinical outcomes and reduced immunogenicity with combination therapy; the main concern is additive immunosuppression increasing infection and hepatotoxicity risk.
対処法
Follow monitoring protocols for both agents: CBC, LFTs every 4–8 weeks; ensure folic acid supplementation with methotrexate; screen for tuberculosis before starting adalimumab; counsel on infection risk.