Halozyme Therapeutics Jumps 2.18% on 146% Volume Spike to 381st Rank as ENHERTU Collaboration Fuels Biotech Buzz

Halozyme Therapeutics (NASDAQ:HALO) surged 2.18% on October 1, 2025, with a trading volume of $330 million, marking a 146.25% increase from the previous day. The biotech stock ranked 381st in terms of trading activity across U.S. equities, reflecting heightened investor interest in the sector.

Analysts attributed the volume spike to renewed focus on Halozyme’s ENHERTU collaboration, which remains under review for regulatory updates. While no direct corporate announcements were reported, the stock’s performance aligned with broader market trends showing increased liquidity in mid-cap biotech names. Short-term traders appeared to capitalize on the volume surge, though no fundamental catalysts were disclosed in the company’s recent filings.

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