Regeneron's $0.38 Billion Volume Plunges 39% to 299th Rank Amid FDA Delays and Legal Battles

On October 7, 2025, Regeneron Pharmaceuticals (REGN) reported a trading volume of $0.38 billion, a 39.47% decline from the previous day, ranking 299th in market activity. The stock closed 0.38% lower, reflecting muted investor engagement amid broader market dynamics.

Recent developments highlight regulatory and operational challenges for the biopharmaceutical giant. A pending FDA review of its flagship diabetes drug, Kevzara, has introduced uncertainty, with analysts noting potential delays in approval timelines. Additionally, ongoing legal disputes with rival firms over patent protections have created short-term volatility, though no new litigation was announced. The company’s pipeline updates, including Phase III trial data for a novel gene therapy, were met with cautious optimism, with investors parsing the therapeutic potential against commercialization risks.

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