A drug that switches off the antibody factories is putting a stubborn kidney disease into early remission

In primary membranous nephropathy, the immune system makes antibodies that attack the kidneys' tiny filters, letting protein leak away and putting the kidneys themselves at risk — and today's treatments fail to bring full remission for most patients. Budoprutug, a drug whose early results were presented at Kidney Week 2026 in Denver, goes after the source instead: it targets CD19, a marker on the B cells that manufacture those harmful antibodies. In Climb Bio's Phase 2 PrisMN trial, patients on the lowest dose, 200 mg, saw those B cells depleted, their PLA2R antibody levels fall, and signs of immunologic remission within 12 weeks, with the drug generally well tolerated so far. In a separate case, a patient with a related kidney condition, minimal change disease, stayed in remission for three years without steroids after treatment.

SDG 3 · Good health and well-being — Mechanism: tech innovation