Jade Biosciences is a clinical-stage biopharmaceutical company developing monoclonal antibody (mAb) therapies for autoimmune diseases. Jade generates no revenue and has no approved products. Its lead program, JADE101, is an anti-APRIL mAb targeting IgA nephropathy (IgAN), a progressive autoimmune kidney disease in which abnormal IgA deposits in the kidney lead to declining kidney function and, in 20-50% of patients within 20 years of diagnosis, end-stage kidney disease. By blocking APRIL — a cytokine that drives overproduction of the pathological IgA — JADE101 is designed to be disease-modifying, rather than symptom-managing. JADE101 entered Phase 1 in healthy volunteers in August 2025, with Phase 2 in IgAN patients planned for mid-2026. The second program, JADE201, is an anti-BAFF-R mAb designed to deplete B cells across multiple autoimmune diseases using a dual mechanism: direct B cell killing and blocking BAFF-driven B cell repopulation. JADE201 is in Phase 1 planning, with a trial expected in Q2 2026. A third program, JADE301, targets an undisclosed pathway and is preclinical. Both JADE101 and JADE201 are engineered with half-life extension technology designed to enable less frequent dosing than existing competitors. Drug discovery rights come from Paragon Therapeutics under a license agreement, and manufacturing is outsourced to WuXi Biologics and Patheon. Jade was formed through a reverse merger in April 2025 and is effectively less than two years old as an operating entity.