Alnylam's brezosiran lowers mutant huntingtin 60-64% in Phase 1b trial
ALNY•Alnylam reported initial Phase 1b results showing brezosiran lowered mutant huntingtin by 60-64% in people with Huntington’s disease. A placebo-controlled pivotal study is planned for 2027, pending regulatory alignment, to assess whether the drug can slow disease progression.
1. Phase 1b findings
Alnylam reported sustained mutant huntingtin lowering with brezosiran in a Phase 1b trial, with encouraging safety and tolerability. The findings support potential twice-yearly dosing and were presented at the European Huntington’s Disease Network Clinical Research Congress 2026. A placebo-controlled pivotal study is planned for 2027, pending regulatory alignment.
