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Effectiveness and Adverse Events of Nirmatrelvir/Ritonavir Versus Molnupiravir for COVID-19 in Outpatient Setting:
Jin Ju Park1, Hyunji Kim2, Yong Kyun Kim3
1Division of Infectious Diseases, Department of Internal Medicine, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
Insights
Nirmatrelvir/ritonavir and molnupiravir showed similar low rates of hospitalization and death in high-risk COVID-19 patients. Nirmatrelvir/ritonavir had more adverse events, though none were severe, suggesting both are safe options.
Area of Science:
- Infectious Diseases
- Pharmacology
- Public Health
Background:
- Coronavirus disease 2019 (COVID-19) poses significant risks to high-risk outpatient populations.
- Oral antiviral agents are crucial for managing COVID-19 in non-hospitalized patients.
- Comparing nirmatrelvir/ritonavir and molnupiravir is essential for optimizing COVID-19 treatment strategies.
Purpose of the Study:
- To compare the effectiveness and safety of nirmatrelvir/ritonavir versus molnupiravir.
- To evaluate hospitalization, death, and adverse event rates in high-risk COVID-19 outpatients.
- To identify patient characteristics influencing treatment outcomes and adverse reactions.
Main Methods:
- A multicenter prospective observational study involved 480 non-hospitalized adult COVID-19 patients.
- Patients received either molnupiravir (n=240) or nirmatrelvir/ritonavir (n=240).
- Outcomes including hospitalization, death, and adverse events were assessed within 28 days.
Main Results:
- Hospitalization and death rates were low and not significantly different between the two groups (0.4% vs. 0.8%).
- Nirmatrelvir/ritonavir was associated with a higher risk of adverse events (OR, 1.96), particularly in older adults (OR, 3.04).
- Adverse events were mild to moderate; in the molnupiravir group, older age and vaccination reduced adverse event occurrence.
Conclusions:
- Both nirmatrelvir/ritonavir and molnupiravir are effective and safe for treating high-risk COVID-19 outpatients.
- Nirmatrelvir/ritonavir demonstrated a higher incidence of adverse events, but none were severe.
- Molnupiravir presents a viable alternative, especially for patients experiencing adverse events with nirmatrelvir/ritonavir.
Background:
In this study, we aimed to compare the effectiveness and adverse reactions of nirmatrelvir/ritonavir and molnupiravir in high-risk outpatients with coronavirus disease 2019 (COVID-19).
Methods:
This multicenter prospective observational study evaluated the rate of hospitalization, death, and adverse events within 28 days of oral antiviral agent prescription (molnupiravir, n = 240; nirmatrelvir/ritonavir, n = 240) to 480 nonhospitalized adult patients with COVID-19 from August 2, 2022 to March 31, 2023.
Results:
Patients receiving molnupiravir had a higher prevalence of comorbidities (85.8% vs. 70.4%; P < 0.001) and a higher Charlson comorbidity index (2.8 ± 1.4 vs. 2.5 ± 1.5; P = 0.009) than those receiving nirmatrelvir/ritonavir. Three patients required hospitalization (nirmatrelvir/ritonavir group, n = 1 [0.4%]; molnupiravir group, n = 2 [0.8%]; P = 1.000). Nirmatrelvir/ritonavir was associated with a higher risk of adverse events than molnupiravir (odds ratio [OR], 1.96; 95% confidence interval [CI], 1.27-3.03), especially for patients aged 65 years and older (OR, 3.04; 95% CI, 1.71-5.39). The severity of adverse events in both groups was mild to moderate and improved after discontinuation of medication. In the molnupiravir group, age ≥ 65 years (OR, 0.43 95% CI, 0.22-0.86) and appropriate vaccination (OR, 0.37; 95% CI, 0.15-0.91) reduced the occurrence of adverse events.
Conclusion:
The rates of hospitalization and death were low and not significantly different between high-risk patients who received either nirmatrelvir/ritonavir or molnupiravir. Although adverse events were more frequent with nirmatrelvir/ritonavir than with molnupiravir, none were severe. Nirmatrelvir/ritonavir can be safely used to treat COVID-19, while molnupiravir could be considered as an alternative treatment option for high-risk groups.
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