Pediatric COVID-19 Treatment: Nirmatrelvir/Ritonavir's Impact on Hospitalization Risk

This study aims to fill a gap in randomized trial data by examining the effectiveness of nirmatrelvir/ritonavir (N/R) in non-hospitalized pediatric patients aged 12–17 years infected with the SARS-CoV-2 Omicron variant. Using a target trial emulation approach, the research assesses the drug's ability to mitigate the risk of all-cause hospitalization in this demographic.

N/R treatment showed a correlation with decreased 28-day all-cause hospitalization rates (absolute risk reduction = 0.23%, 95% CI = 0.19%–0.31%; relative risk = 0.66, 95% CI = 0.56–0.71). Importantly, there was no mortality, in-hospital disease progression, or adverse clinical outcomes among those receiving treatment.

According to the investigators,” In this highly vaccinated cohort, the cumulative incidences of all-cause hospitalization following SARS-CoV-2 Omicron variant infection in the paediatric population were considerably low, accounting for only 0.45% of N/R group and 0.68% of control group.”¹

The analysis included 49,378 eligible pediatric patients from March 16, 2022, to February 5, 2023, meeting specified age and infection criteria. Exposure was defined as outpatient treatment with N/R within 5 days of symptom onset or COVID-19 diagnosis. Primary outcome measures were 28-day all-cause mortality or all-cause hospitalization, with secondary outcomes including 28-day in-hospital disease progression, COVID-19-specific hospitalization, multisystem inflammatory syndrome in children (MIS-C), acute liver injury, acute renal failure, and acute respiratory distress syndrome.

“The cumulative incidence of all-cause hospitalization among our nirmatrelvir/ritonavir users (0.45%) was comparatively <5.7% observed in a US paediatric patient cohort (without a control group) from 1st December 2021–29th September 2022, where 64% of their nirmatrelvir/ritonavir recipients had pre-existing chronic diseases,” according to investigators.1

Drawing from previous reporting by Contagion, which highlights the therapeutic potential of N/R for acute COVID-19 infections in reducing the incidence of Post-COVID Conditions (PCC) or Long COVID, Alexandra F. Dalton, PhD, discusses her observational study based on healthcare data. Her research suggests that the drug may effectively decrease the occurrence of Long COVID, particularly among younger adults, adolescents, and other older age groups.

“We saw in younger adults that there wasn't really much of a statistically meaningful relationship between Paxlovid use and overall PCC,” Dalton said. “And when we looked at individual conditions, we saw a few where it looked like there was a reduced risk and a few where there's an increased risk. And then among adolescents, there were just a handful of individual conditions where we saw increased risk."²

In conclusion, the effectiveness of N/R reduces the risk of hospitalization without observed mortality or adverse outcomes, offering valuable insights for combating COVID-19, especially among children. Further research will refine our understanding of antiviral therapies and their role in managing diverse patient cohorts.

References

1. Wong C, Lau K, Au I, et. al. Effectiveness of nirmatrelvir/ritonavir in children and adolescents aged 12–17 years following SARS-CoV-2 Omicron infection: A target trial emulation. Nature Communications. Published June 8, 2024. Accessed June 12, 2024. https://www.nature.com/articles/s41467-024-49235-8

2. Parkinson, J. Does Paxlovid Use In Adults and Children Reduce the Incidence of Long COVID? Contagion. Published October 14, 2023. Accessed June 12, 2024. https://www.contagionlive.com/view/does-paxlovid-use-in-adults-and-children-reduce-the-incidence-of-long-covid-