Alnylam Pharmaceuticals Shares Fall 1.92% to 58.45 Slumps to 368th in Market Activity Amid Biotech Sector Rotation

On September 25, 2025, Alnylam Pharmaceuticals (ALNY) closed with a 1.92% decline, trading at $58.45 as of 16:15 ET. The stock saw a trading volume of 0.31 billion shares, a 31.08% drop from the previous day, ranking 368th in market activity. The underperformance came amid mixed investor sentiment surrounding the biotech sector, though no direct corporate announcements were reported to influence the movement.

Analysts noted that the decline could be linked to broader market rotation toward defensive assets, with healthcare stocks facing profit-taking pressures. Institutional trading data showed reduced participation from key hedge fund managers, which historically correlates with short-term volatility. The stock’s recent performance remains anchored to its pipeline progress, particularly the regulatory timeline for its Givosiran program, though no new data was disclosed to impact near-term positioning.

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