A single dose cut the protein that drives Huntington's disease by up to 83% — and the effect is lasting

Huntington's disease is caused by a faulty protein that slowly damages the brain, and no approved treatment yet slows it. Alnylam's experimental therapy brezosiran uses gene-silencing technology — a molecule that switches off the faulty gene's instructions. In early Phase 1b results presented at the European Huntington's Disease Network congress in Kraków, the 48 participants' spinal fluid levels of the mutant protein fell by an average of 60 to 64% at three months in the highest dose group, with one person reaching 83%. The effect appears durable enough that dosing might be needed only twice a year. The company is planning a larger trial in 2027 to test the question that matters most: whether lowering the protein slows the disease itself.

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