Regeneron Stock Slumps as Trading Volume Plunges 31% to 440M Ranking 207th in U.S. Activity

On August 18, 2025, Regeneron Pharmaceuticals (REGN) closed with a 1.12% decline, trading on a daily volume of $440 million—down 31.45% from the prior day. The stock ranked 207th in trading activity among U.S. equities, reflecting reduced investor engagement amid broader market fluctuations.

Recent developments highlighted potential catalysts for near-term volatility. A regulatory update indicated the FDA may delay final approval of Regeneron's experimental Alzheimer's therapy, Kuhak, due to ongoing data review concerns. Analysts noted this could impact Q4 2025 revenue projections, though the company emphasized no clinical setbacks. Concurrently, a partnership announcement with a biotech firm to co-develop rare disease treatments generated mixed reactions, with investors balancing long-term growth prospects against short-term capital allocation risks.

Technical indicators showed bearish momentum, with the 20-day moving average crossing below key support levels. Short interest data revealed a 7.2% increase in open shorts over two weeks, suggesting heightened bearish sentiment. However, institutional ownership remains stable at 68%, with no significant hedge fund position changes reported in the latest filings.

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