Regeneron Shares Fall 1.12% Amid $1.29 Billion Volume Spike, Ranking 167th in U.S. Equity Value Trading

On September 19, 2025, Regeneron Pharmaceuticals (REGN) closed at a 1.12% decline with a trading volume of $1.29 billion, a 70.96% surge from the previous day’s volume. The stock ranked 167th in total trading value among U.S. equities, reflecting heightened investor activity despite the downward price movement.

Analysts attributed the volume spike to a combination of institutional rebalancing and short-term speculative positioning ahead of pending FDA advisory committee meetings. The biotech giant’s recent pipeline disclosures, including Phase III results for a novel oncology therapy, failed to offset broader sector weakness driven by macroeconomic concerns and bond yield volatility.

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