Alnylam results open door to larger amyloidosis indication, lifting shares

New Phase III results could lead to a label expansion for Alnylam’s RNAi therapy Onpattro as soon as next year, giving the amyloidosis drug a path to reach a much larger population of patients with the disorder as the biotech aims to build a multi-billion dollar franchise.

The closely watched readout propelled shares of Alnylam Pharmaceuticals Inc. (NASDAQ:ALNY) up 49% Wednesday, equating to a gain of about $8.4 billion in market cap. The news helped lift biotech indexes by about 4%; buysiders surveyed by BioCentury early this summer had frequently mentioned Alnylam’s study as an important catalyst that could drive broader investor sentiment in the sector...