Celldex Therapeutics Inc.'s stock plunged 51% in active premarket trade Monday, after an independent panel recommended that the company discontinue the late-stage trial of its brain cancer treatment following disappointing trial results. Volume was already over 760,000 shares about 75 minutes before the open, to make it the fourth-most active stock in the premarket session. An independent data safety and monitoring board has determined that the Phase 3 study of Rintega will not reach its primary endpoint statistical significance for overall survival. Celldex said it would discontinue the study. "We are extremely disappointed for patients that the ACT IV study was not successful," said Chief Executive Anthony Marucci. "While this is certainly not the desired outcome, we remain steadfast believers in the power of immunotherapy to transform the future of cancer treatment." The stock had tumbled 48% year to date through Friday, and 72% over the last year, while the S&P 500 has slipped 4.8% in the year.
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