Antiviral Effects of TXA as a Preventative Treatment Following COVID-19 Exposure

A recent report in Physiolological Reviews proposed that the endogenous protease plasmin acts on SARS-CoV-2 by cleaving a newly inserted furin site in the S protein portion of the virus resulting in increased infectivity and virulence. A logical treatment that might blunt this process would be the inhibition of the conversion of plasminogen to plasmin. Fortunately, there is an inexpensive, commonly used drug, tranexamic acid, TXA, which suppresses this conversion and could be re-purposed for the treatment of COVID-19. TXA is a synthetic analog of the amino acid lysine which reversibly binds four to five lysine receptor sites on plasminogen. This reduces conversion of plasminogen to plasmin, and is normally used to prevent fibrin degradation. TXA is FDA approved for the outpatient treatment of heavy menstrual bleeding (typical dose 1300 mg p.o. TID x 5 days) and off-label use for many other indications. TXA is used perioperatively as a standard-of-care at UAB for orthopedic and cardiac bypass surgeries. It has a long track record of safety such that it is used over-the-counter in other countries as an antiviral and for the treatment of cosmetic dermatological disorders. Given the potential benefit and limited toxicity of TXA it would appear warranted to perform randomized, double-blind placebo controlled exploratory trial at UAB as a prophylactic antiviral treatment following exposure to COVID-19 in order to determine whether it reduces infectivity and virulence of the SARS-CoV-2 virus as hypothesized. Involvement of each patient is only for 7 days before primary endpoints and 30 days for final data collection.