Paxlovid Dosing for Patients with Moderate Renal Impairment (eGFR 44)
For a patient with moderate renal impairment (eGFR of 44 mL/min/1.73 m²), the recommended dosing of Paxlovid is 150 mg nirmatrelvir with 100 mg ritonavir twice daily for 5 days. 1
Rationale for Dose Adjustment
Nirmatrelvir, the active antiviral component of Paxlovid, is primarily eliminated by the kidneys. When renal function is impaired, the following considerations apply:
- Pharmacokinetic impact: In patients with moderate renal impairment (eGFR 30-60 mL/min), nirmatrelvir exposure increases by approximately 87% compared to those with normal renal function 2
- FDA-approved dosing: The FDA label specifically recommends dose reduction for patients with moderate renal impairment 1
- Dose pack availability: A specific dose pack for moderate renal impairment containing nirmatrelvir 150 mg and ritonavir 100 mg is available 1
Dosing Algorithm Based on Renal Function
| Renal Function | eGFR Range (mL/min) | Nirmatrelvir Dose | Ritonavir Dose | Frequency |
|---|---|---|---|---|
| Normal to mild impairment | ≥60 | 300 mg (two 150 mg tablets) | 100 mg | Twice daily |
| Moderate impairment | ≥30 to <60 | 150 mg (one 150 mg tablet) | 100 mg | Twice daily |
| Severe impairment | <30 | 150 mg | 100 mg | Once daily |
Administration Guidelines
- Treatment should be initiated as soon as possible after COVID-19 diagnosis and within 5 days of symptom onset
- All tablets should be taken together at the same time, twice daily
- Can be taken with or without food
- Tablets should be swallowed whole and not chewed, broken, or crushed
- Complete the full 5-day treatment course
Monitoring Recommendations
For patients with moderate renal impairment receiving Paxlovid:
- Monitor renal function during treatment
- Watch for potential drug-drug interactions, as ritonavir is a strong CYP3A inhibitor
- Assess for adverse effects, particularly those that may be exacerbated by higher nirmatrelvir concentrations
Important Considerations
- Drug interactions: Prior to prescribing, review all medications the patient is taking to assess for potential interactions with ritonavir 1
- Safety profile: Studies have shown that the adjusted dose is well-tolerated in patients with renal impairment 2, 3
- Clinical efficacy: The dose-adjusted regimen maintains therapeutic nirmatrelvir concentrations while avoiding excessive exposure 4
Common Pitfalls to Avoid
- Using standard dosing: Administering the standard dose (300 mg nirmatrelvir) to patients with moderate renal impairment can lead to excessive drug exposure and potential toxicity
- Inappropriate dose timing: On hemodialysis days (for patients with severe renal impairment), Paxlovid should be administered after hemodialysis 1
- Overlooking drug interactions: Failure to review and adjust concomitant medications that interact with ritonavir
The evidence strongly supports that patients with moderate renal impairment (eGFR 44) should receive the reduced dose of nirmatrelvir (150 mg) with standard ritonavir (100 mg) twice daily to maintain efficacy while ensuring safety.