argenx Shares Plunge on $280M Trade Volume Ranks 447th in Liquidity Amid Regulatory Scrutiny

On September 17, 2025, , ranking 447th among U.S. stocks by liquidity. The biotech firm's shares underperformed as investors digested recent developments in its clinical pipeline and regulatory landscape.

Recent filings highlighted ongoing Phase III trials for enoblitinib in non-small cell lung cancer, . Analysts noted the trial design incorporates biomarker-stratified cohorts, a strategic shift that could refine patient selection but may delay broader label approvals. Concurrently, the FDA's recent guidance on adaptive trial methodologies introduced procedural uncertainties for accelerated pathways.

Regulatory risks remain elevated as the European Commission initiated a post-marketing review of enoblitinib's safety profile following rare but severe adverse event reports. While the drug maintains conditional approval in the EEA, the review could trigger labeling restrictions or additional clinical requirements. Short-term technical indicators suggest continued volatility amid these regulatory overhangs.

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