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Published on: November 5, 2021
Oral antivirals for the prevention and treatment of SARS-CoV-2 infection
Vicente Soriano1, Carmen de-Mendoza2, Benson Edagwa3
1UNIR Health Sciences School & Medical Center, Madrid, Spain.
Abstract:
Vaccines and antivirals are the classical weapons deployed to contain, prevent, and treat life-threatening viral illnesses. Specifically, for SARS-CoV-2 infection, vaccines protect against severe COVID-19 disease manifestations and complications. However, waning immunity and emergence of vaccine escape mutants remains a growing threat. This is highlighted by the current surge of the omicron COVID-19 variant. Thus, there is a race to find treatment alternatives. We contend that oral small molecule antivirals that halt SARSCoV- 2 infection are essential. Compared to currently available monoclonal antibodies and remdesivir, where parenteral administration is required, oral antivirals offer treatments in an outpatient setting with dissemination available on a larger scale. In response to this need at 2021's end, regulatory agencies provided emergency use authorization for both molnupiravir and nirmatrelvir. These medicines act on the viral polymerase and protease, respectively. Each is given for 5 days and can reduce disease progression by 30% and 89%, respectively. The advent of additional oral antivirals, the assessment of combination therapies, the formulation of extended-release medications, and their benefit for both early treatment and prophylaxis will likely transform the landscape of the COVID-19 pandemic.
Insights
Oral antivirals like molnupiravir and nirmatrelvir offer crucial alternatives for treating SARS-CoV-2 infection, especially with waning vaccine immunity and emerging variants. These small molecule drugs provide accessible outpatient treatment options to combat COVID-19 progression.
Area of Science:
- Virology
- Infectious Diseases
- Pharmacology
Background:
- Vaccines and antivirals are key for managing viral illnesses like SARS-CoV-2.
- Waning immunity and emergent variants (e.g., Omicron) necessitate alternative treatments.
- Current treatments like monoclonal antibodies and remdesivir require parenteral administration.
Purpose of the Study:
- To highlight the essential role of oral small molecule antivirals for treating SARS-CoV-2 infection.
- To discuss the advantages of oral antivirals in outpatient settings.
- To review recent advancements in oral antiviral therapies for COVID-19.
Main Methods:
- Review of existing literature on SARS-CoV-2 treatments.
- Analysis of emergency use authorizations for molnupiravir and nirmatrelvir.
- Comparison of oral antivirals with parenteral therapies.
Main Results:
- Molnupiravir and nirmatrelvir received emergency use authorization in late 2021.
- Molnupiravir targets viral polymerase, reducing progression by 30%.
- Nirmatrelvir targets viral protease, reducing progression by 89%.
Conclusions:
- Oral antivirals are essential for accessible COVID-19 treatment.
- Combination therapies and extended-release formulations show promise.
- Oral antivirals are expected to significantly impact the COVID-19 pandemic landscape.
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