Tempest Therapeutics shares fall 12.26% after-hours as all-stock CAR-T acquisition raises dilution concerns amid low valuation.

Tempest Therapeutics (NASDAQ: TPST) fell 12.26% in after-hours trading following the completion of its all-stock acquisition of dual-targeting CAR-T assets from Factor Bioscience Inc. The transaction, which includes clinical-stage TPST-2003, was executed at a time when the stock trades near its 52-week low, raising concerns about valuation and dilution risks for existing shareholders. The micro-cap biotech, valued at $11.6 million, funded the deal entirely through equity, potentially signaling overleveraging or asset overvaluation to investors. While the acquisition expands Tempest’s pipeline with next-generation CAR-T therapies, the lack of immediate financial upside and reliance on strategic partners for development costs may have dampened enthusiasm. The press release highlighted the strategic move but did not address short-term capital constraints or competitive positioning, contributing to the bearish after-hours reaction.