Traws Pharma falls after FDA puts flu drug application on clinical hold

Shares of Traws Pharma TRAW.O down 20.81% at $1.58 premarket

Co says the U.S. FDA placed on clinical hold its investigational new drug application for tivoxavir marboxil, a single oral tablet for prevention of seasonal influenza

Adds that FDA flagged concerns "with the mutagenicity data package" for drug in application

Also says it filed the application to allow the government's biomedical research unit to fully review its bid for inclusion in the strategic stockpile for avian‑flu treatment

Clinical hold does not directly impact ongoing and planned studies outside of the United States; working to mitigate issue in clinical development plan - TRAW

TRAW shares up 74.3% YTD