First-generation oral antivirals against SARS-CoV-2

Background: Oral drugs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have received emergency use authorization for the treatment of mild-to-moderate COVID-19 in non-hospitalized patients who are at high risk for clinical progression.

Objectives: To provide a clinical practice overview of first-generation oral antiviral agents against SARS-CoV-2.

Sources: References for this review were identified through searches of PubMed, Google Scholar, bioRxiv, medRxiv, regulatory drug agencies, and pharmaceutical companies' websites up to 16 February 2022.

Content: Molnupiravir and nirmatrelvir and ritonavir have been authorized for use in nonhospitalized individuals with mild-to-moderate COVID-19 who are at high risk for progression. In clinical trials, molnupiravir reduced the frequency of hospitalization or death by 3% (relative risk reduction 30%), and nirmatrelvir and ritonavir by 6% (relative risk reduction 89%). Their use in clinical practice requires early administration, review of drug-drug interactions (nirmatrelvir and ritonavir), considerations of embryo-fetal toxicity (molnupiravir), and compliance with ingestion of a high number of pills. Knowledge gaps include the efficacy of these agents in vaccinated, hospitalized, or immunosuppressed individuals with prolonged SARS-CoV-2 persistence.

Implications: First-generation oral antivirals represent progress in therapeutics against SARS-CoV-2, but also pose new challenges in clinical practice. Further advances in the development of new drugs are required.