Pfizer Slumps 2.25% on 10/8 as Regulatory Delays and R&D Cuts Weigh on Pharma Giant $1.24B Volume Ranks 74th in U.S. Liquidity

Pfizer (PFE) closed 2.25% lower on October 8, 2025, with a trading volume of $1.24 billion, ranking 74th among U.S. stocks by liquidity. The decline followed mixed signals from regulatory filings and clinical updates affecting market sentiment for the pharmaceutical giant.

Analysts noted that recent filings highlighted potential delays in the approval timeline for a key oncology candidate, raising concerns about revenue visibility in 2026. Additionally, a downward revision in third-quarter R&D spending projections underscored short-term cost pressures, though long-term pipeline metrics remained within guidance ranges.

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