Simponi is a prescription medication containing golimumab, a human monoclonal IgG1 antibody that targets tumor necrosis factor-alpha (TNF-α). It is supplied as a solution for injections 50 mg/0.5 mL in a pre-filled syringe. Simponi is used for treating active, severe, and progressive rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and moderate-to-severe ulcerative colitis in adults. The drug works as a TNF inhibitor with potent anti-inflammatory and immunomodulatory effects, administered via subcutaneous injection typically once every two weeks.