Celldex sinks after halting GBM Phase III

Celldex Therapeutics Inc. (NASDAQ:CLDX) fell $4.40 (54%) to $3.79 on Monday after it said it will stop the Phase III ACT IV trial of Rintega rindopepimut to treat newly diagnosed glioblastoma multiforme. The decision followed an interim DSMB analysis that showed Rintega will not significantly improve overall survival (OS) vs. control, the primary endpoint, in patients with minimal residual disease.

Celldex said the analysis showed the study's Rintega and control arms "are performing on par with each other." Interim OS was 20.4 months for Rintega and 21.1 months for control (HR=0.99). The company said Rintega performed consistently with prior Phase II trials but that the control arm "significantly outperformed expectations." ...