Molnupiravir Safety in a 75-Year-Old Patient with Impaired Renal Function (GFR < 60)
Molnupiravir can be safely administered to a 75-year-old patient with impaired renal function (GFR < 60 mL/min) without dose adjustment, as it has been shown to have similar pharmacokinetic profiles in patients with renal impairment compared to those with normal renal function. 1
Evidence for Safety in Renal Impairment
Recent pharmacokinetic data specifically examining molnupiravir in patients with renal impairment provides strong support for its use in this population:
- A 2024 phase 1 trial demonstrated that the pharmacokinetics of molnupiravir and its active metabolite (NHC) were similar in participants with severe renal impairment compared to healthy controls 1
- The 90% confidence interval for the geometric mean ratio of plasma NHC area under the concentration-time curve was <2.0 for participants with severe renal impairment versus healthy controls 1
- No dose adjustment is required for molnupiravir in patients with renal impairment of any severity 2
Clinical Experience in Kidney Disease Patients
Clinical evidence further supports the safety profile:
- A retrospective observational study of molnupiravir in hemodialysis patients and kidney transplant recipients showed no serious side effects and rapid resolution of COVID-19 symptoms within 24-48 hours of starting treatment 3
- When compared with nirmatrelvir-ritonavir in patients with advanced kidney disease (eGFR <30 mL/min), molnupiravir showed similar rates of adverse outcomes including ICU admission, ventilatory support, hepatic impairment, ischemic stroke, and myocardial infarction 4
Advantages Over Other COVID-19 Antivirals in Renal Impairment
Molnupiravir offers advantages over other COVID-19 antivirals for patients with renal impairment:
- Unlike nirmatrelvir/ritonavir, which requires dose reduction in moderate renal impairment and is not recommended in severe renal impairment, molnupiravir does not require dose adjustment 2
- Remdesivir has traditionally not been recommended below eGFR <30 mL/min, making molnupiravir a more straightforward option for patients with significant renal impairment 2
Monitoring Recommendations
While molnupiravir is safe in renal impairment, general principles for medication management in patients with kidney disease should be followed:
- Monitor respiratory status and mental status regularly 5
- Watch for any signs of toxicity, although these are not expected with molnupiravir specifically 5
- Consider scheduling medication administration after dialysis sessions if the patient is on dialysis therapy 5
Conclusion
For a 75-year-old patient with impaired renal function (GFR < 60 mL/min), molnupiravir can be safely administered at the standard dose of 800 mg every 12 hours for 5 days without adjustment. The pharmacokinetic profile remains similar to patients with normal renal function, and clinical experience supports its safety and efficacy in this population.