Traws Pharma shares fall 19.8% intraday as FDA places tivoxavir marboxil on clinical hold.

Traws Pharma (NASDAQ:TRAW) tumbled 19.80% intraday after the U.S. FDA placed a clinical hold on its influenza treatment tivoxavir marboxil over mutagenicity concerns, with the agency scheduled to outline specific issues by March 16, 2026. This negative regulatory development overshadowed positive updates on its COVID-19 drug ratutrelvir, which showed improved tolerability and faster symptom resolution versus PAXLOVID in Phase 2 trials. While ratutrelvir’s results were favorable, the FDA’s hold on tivoxavir—its key pipeline asset—directly triggered the sharp decline, as investors reassessed the company’s near-term prospects.