Orencia (abatacept) is a biologic disease-modifying antirheumatic drug (DMARD) used to manage autoimmune conditions such as moderate to severe rheumatoid arthritis (RA), psoriatic arthritis (PsA), and moderate to severe polyarticular juvenile idiopathic arthritis (pJIA). It works by selectively modulating a key immune pathway involved in the activation of T-cells, which are crucial in the inflammatory process that leads to joint damage. By inhibiting this pathway, Orencia helps reduce inflammation, alleviate symptoms, slow disease progression, and improve physical function. It is available as an intravenous infusion or subcutaneous injection and is typically prescribed when conventional treatments are inadequate or ineffective.