Antivirals for COVID-19.

Drugs targeting RNA respiratory viruses has resulted in few effective therapies, highlighting challenges for antivirals to treat COVID-19. Several antivirals are being investigated for symptomatic COVID-19 but no definitive data support their clinical use. Remdesivir, with good in vitro activity against SARS-CoV2, appeared to result in favorable outcomes for hospitalized patients in a compassionate use series with shortened time to recovery and a modest decrease in mortality. Currently, remdesivir is available in phase III clinical trials, the compassionate use program, and eventually through the emergency use authorization. A randomized controlled trial of lopinavir/ritonavir demonstrated no apparent clinical or virologic benefit and drug-drug interactions and side effects further limit its utility. Antivirals to treat influenza (oseltamivir) have limited activity against SARS-CoV-2, but favipiravir and umifenovir, influenza antivirals available internationally, have distinct viral targets and require further investigation. Antivirals with evidence of clinical activity must be studied as treatment and prophylaxis for those at high risk for severe COVID-19.