Alnylam Pharmaceuticals Inc.’s decision to change its analysis plan for the phase III Helios-B trial of RNAi therapeutic Amvuttra (vutrisiran) to treat transthyretin amyloidosis with cardiomyopathy, pushing top-line results back by three months, pressured its share price (NASDAQ:ALNY) down by 10% on Feb. 15, while also boosting shares of competitor Bridgebio Pharma Inc. (NASDAQ:BBIO) by 14%.