SIT-047

SIT-047 is a novel, oral, small molecule inhibitor of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2), an enzyme central to one-carbon metabolism. Developed by Sitryx Therapeutics, SIT-047 is designed as a first-in-class disease-modifying therapy for psoriatic arthritis and potentially other autoimmune diseases. By inhibiting MTHFD2, SIT-047 modulates the activity of Th1 and Th17 immune cell subsets that drive inflammation in psoriatic arthritis. Preclinical studies have shown strong efficacy and favorable tolerability, supporting its progression into regulatory non-clinical studies with clinical trial authorization targeted for 2026. Beyond psoriatic arthritis, SIT-047 may have therapeutic potential in rheumatoid arthritis, lupus (systemic lupus erythematosus), Crohn’s disease, ulcerative colitis, and atopic dermatitis[1][3][5][7].