TXA and Corona Virus 2019 (COVID19) in Outpatients

A recent report in Physiological Reviews proposed that the endogenous protease plasmin acts on the COVID19 virus by cleaving a newly inserted furin site in the S protein portion of the virus resulting in increased infectivity and virulence. Patients with hypertension, diabetes, coronary artery disease, cerebrovascular illness, lung disease and kidney dysfunction commonly have elevated levels of plasmin/plasminogen and it was proposed that this may be the mechanism for poorer outcomes in patients with these co-morbidities. A logical treatment that might blunt this process would be the inhibition of the conversion of plasminogen to plasmin. There is an inexpensive, commonly used drug, tranexamic acid, (TXA), which suppresses this conversion and could be re-purposed for the treatment of COVID19.

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 treatment of heavy menstrual bleeding (typical dose 1300 mg p.o. three times per day x 5 days) and off-label use for many other indications. TXA is used perioperatively as a standard-of-care at the University of Alabama at Birmingham (UAB) for orthopedic and cardiac bypass surgeries. At our institution, it is commonly employed in hemorrhaging trauma patients and currently is being studied for perioperative use in Cesarean section surgeries. It has also been utilized for spinal surgery, neurosurgery, orthognathic surgeries and even long term for the treatment of cosmetic dermatological disorders with a long track record of safety. Given the potential benefit and limited toxicity of TXA it would appear warranted to perform a rapid randomized, double-blind placebo controlled exploratory trial at UAB in the treatment of the early phases of COVID19 to determine whether it reduces infectivity and virulence of the COVID19 virus as hypothesized. Involvement of each patient is only for 7 days before primary endpoints.

An exploratory, randomized, placebo-controlled, double-blind Phase 2 clinical trial in which study patients have just been diagnosed with COVID19 as an outpatient. The overall goal of this exploratory study is to assess both safety and efficacy of 5 days of TXA versus placebo in the COVID19 population. All patients would also receive apixaban 5 mg p.o. BID. The primary endpoint for the study would be a need for hospitalization. Contact would consist of daily phone contact. Care for COVID19 would otherwise be standard of care.