New Research on COVID-19 Treatment Efficacy

Strategic Insights -

Recent studies have shed light on the efficacy of COVID-19 treatments, particularly with regards to the combination of molnupiravir and nirmatrelvir-ritonavir. A target trial emulation study published in the International Journal of Infectious Diseases found that while this combination may reduce viral shedding and enhance survival in preclinical studies, it does not significantly reduce mortality, ICU admissions, or ventilatory support needs in hospitalised COVID-19 adults. In contrast, nirmatrelvir-ritonavir monotherapy has been shown to significantly reduce mortality risk, lower risks of acute liver injury, kidney injury, and hyperglycaemia, and may be a more effective treatment option.

Key Takeaways:

  • The study analyzed data from 28,355 patients aged 18 and older, treated within five days of hospital admission between March 16, 2022, and March 31, 2024.
  • Nirmatrelvir-ritonavir monotherapy significantly reduced mortality risk (HR: 0.62; 95% CI 0.50-0.77; ARR: -3.16%) compared to combination therapy.
  • Nirmatrelvir-ritonavir monotherapy also lowered the risks of acute liver injury (HR: 0.53 [95% CI 0.32-0.88]), kidney injury (HR: 0.61 [95% CI 0.51-0.74]), and hyperglycaemia (HR: 0.73 [95% CI 0.57-0.93]).
  • The study found no significant differences in ICU admission or ventilatory support needs between combination therapy and nirmatrelvir-ritonavir monotherapy.
  • The research was conducted by a team of researchers from the University of Hong Kong, led by Ming Hong Choi.
  • The study was commissioned by The Health & Medical Research Fund and received funding from The Health & Medical Research Fund Commissioned Research on COVID-19 (COVID1903010, COVID1903011; COVID19F01).

Statistics:

  • 28,355 patients were analyzed in the study, all of whom were treated within five days of hospital admission.
  • The study found a significant reduction in mortality risk with nirmatrelvir-ritonavir monotherapy, with a hazard ratio of 0.62 (95% CI 0.50-0.77).
  • Nirmatrelvir-ritonavir monotherapy also reduced the risk of acute liver injury, kidney injury, and hyperglycaemia.
  • The study was conducted over a two-year period, from March 16, 2022, to March 31, 2024.

Sources:

  • Comparative Effectiveness of Combination Therapy with Nirmatrelvir-Ritonavir and Molnupiravir versus Monotherapy with Molnupiravir or Nirmatrelvir-Ritonavir in Hospitalised COVID-19 Patients: A Target Trial Emulation Study. International Journal of Infectious Diseases, 2025:108097.
  • Elsevier Sci Ltd, 125 London Wall, London, England (publisher of the International Journal of Infectious Diseases).