By late March 2020 , four potential antiviral therapies – favipiravir , remdesivir , C and hydroxychloroquine ( or chloroquine ) – were in the final stage of human testing – Phase III-IV clinical trials – and several possible vaccines had entered the first stage of human safety evaluation , Phase I . On 21 March , the United States Centers for Disease Control and Prevention ( CDC ) issued a physician advisory concerning remdesivir for people hospitalized with pneumonia caused by COVID-19 : `` While clinical trials are critical to establish the safety and efficacy of this drug , clinicians without access to a clinical trial may request remdesivir for compassionate use through the manufacturer for patients with clinical pneumonia .
Lopinavir was considered among the potential antiviral drugs to treat the COVID-19 before April 2020 .