From the Guidelines
Paxlovid (nirmatrelvir/ritonavir) is currently considered more effective than sotrovimab for COVID-19 treatment, particularly against dominant variants, and is the preferred option due to its maintained effectiveness, oral administration route, and strong clinical evidence supporting its use in preventing severe COVID-19 outcomes. The evidence from recent studies, including those published in the Annals of Internal Medicine 1, suggests that Paxlovid reduces the risk of hospitalization and death by approximately 89% in high-risk patients when started within 5 days of symptom onset. In contrast, sotrovimab, a monoclonal antibody given as a single IV infusion, has significantly reduced effectiveness against newer Omicron variants. Key considerations for the use of Paxlovid include:
- Typical regimen: 300mg nirmatrelvir plus 100mg ritonavir taken twice daily for 5 days
- Important drug interactions due to the ritonavir component
- Requires dose adjustment in kidney disease
- Strong clinical evidence supporting its use in preventing severe COVID-19 outcomes In the context of current clinical practice, the use of Paxlovid is recommended over sotrovimab for the treatment of COVID-19 in outpatient settings, particularly for patients at high risk of progressing to severe disease. This recommendation is based on the most recent and highest-quality evidence available, including the studies cited above 1.
From the Research
Comparison of Sotrovimab and Paxlovid Efficacy
- The efficacy of Sotrovimab (VIR-9011, VIR-7095, monoclonal antibody) and Paxlovid (Nirmatrelvir, antiviral medication) in treating COVID-19 has been studied in various research papers 2, 3, 4, 5, 6.
- A study published in Pharmaceuticals (Basel, Switzerland) in 2023 found that both Molnupiravir and Nirmatrelvir/Ritonavir (Paxlovid) were effective in preventing hospital admission and mortality attributable to COVID-19, with hospitalization rates of 2.0% and 0% respectively, compared to 7.2% in the control group 2.
- Another study published in Viruses in 2023 found that Sotrovimab reduced the risk of COVID-19-related hospitalization or death in patients with mild to moderate COVID-19 Omicron BA.1 and BA.2 subvariant infections, with a significantly lower requirement for oxygen therapy in the treatment group compared to the control group 3.
- A study published in medRxiv in 2022 found that Sotrovimab treatment was associated with a 63% decrease in the odds of all-cause hospitalization and an 89% decrease in the odds of all-cause 28-day mortality among COVID-19 outpatients during the Delta variant phase 4.
- A study published in The Journal of infectious diseases in 2022 found similar results, with Sotrovimab treatment associated with a 63% decrease in the odds of all-cause hospitalization and an 89% decrease in the odds of all-cause 28-day mortality among COVID-19 outpatients during the Delta variant phase 5.
- A study published in Annals of medicine in 2025 found that early combination of Sotrovimab with Nirmatrelvir/Ritonavir or Remdesivir was associated with a low rate of persisting SARS CoV-2 infection in immunocompromised outpatients with mild-to-moderate COVID-19, with no patients hospitalized within 30 days of disease onset or requiring oxygen administration 6.
Key Findings
- Sotrovimab and Paxlovid have been shown to be effective in preventing hospital admission and mortality attributable to COVID-19 2, 3, 4, 5, 6.
- Sotrovimab has been found to reduce the risk of COVID-19-related hospitalization or death in patients with mild to moderate COVID-19 Omicron BA.1 and BA.2 subvariant infections 3.
- Paxlovid has been found to be effective in preventing hospital admission and mortality attributable to COVID-19, with a hospitalization rate of 2.0% compared to 7.2% in the control group 2.
- The combination of Sotrovimab with Nirmatrelvir/Ritonavir or Remdesivir has been found to be effective in preventing hospitalization, progression to severe COVID-19, and development of prolonged/persisting SARS-CoV-2 infection in immunocompromised patients 6.