Shares of Aprea Therapeutics Inc. (NASDAQ:APRE), a company focused on developing therapies that reactivate the mutant tumor suppressor protein p53, fell 78.1% to $5.50 on Dec. 28, just north of its cash balance, after a pivotal trial of its lead candidate missed its endpoint, leaving the asset's future hazy and likely scuttling plans the company had for a first quarter 2021 NDA filing.