This is a single are and single-center tolerability study of high dose leflunomide therapy in
outpatient adult participants with mild COVID-19. In vitro studies have shown antiviral
effects of leflunomide against SARS CoV-2, but the clinical outcomes in the disease have been
variable. Our hypothesis is that targeting high risk patients earlier in the disease course
and with a higher dose regimen are both required to see improvement in disease outcome
measures in COVID-19. This study aims to prove the tolerability of high dose leflunomide in
this setting.

Patients are selected based on identification of mild COVID-19 symptoms. Investigators will
enroll twenty patients and perform a detailed Tele-helath interview to ensure they meet
eligibility criteria and provide informed consent. 100 mg leflunomide daily for three days
followed by 30 mg day will be prescribed. The subjects will be required to monitor their
temperatures twice daily and a daily telephone call with an investigatory will review
symptoms of disease and potential side effects of the drug. Subjects can discontinue the drug
after five days if they no longer have fever, or take the drug for up to ten days if required
for fever resolution.