From the Guidelines
Paxlovid (nirmatrelvir/ritonavir) should be initiated as soon as possible after diagnosis of COVID-19 and within 5 days of symptom onset. This recommendation is based on the most recent evidence from the American College of Physicians, which suggests that early initiation of Paxlovid is crucial for maximum effectiveness in preventing viral replication in the early stages of infection 1. The standard adult dosage is nirmatrelvir 300 mg (two 150 mg tablets) with ritonavir 100 mg (one tablet), taken together twice daily for 5 days.
Key Considerations for Paxlovid Initiation
- Paxlovid is primarily recommended for patients at high risk for progression to severe COVID-19, including older adults (particularly those over 65), unvaccinated individuals, and those with underlying medical conditions such as diabetes, heart disease, lung disease, obesity, or immunocompromised states.
- Before prescribing, clinicians should carefully review the patient's medication list for potential drug interactions, as ritonavir is a strong CYP3A inhibitor that can affect metabolism of many medications.
- Dose adjustments are necessary for patients with moderate renal impairment (eGFR 30-60 mL/min), while Paxlovid is not recommended for those with severe renal impairment (eGFR <30 mL/min) or severe hepatic impairment.
- The medication should be taken with or without food, and patients should complete the full 5-day course even if symptoms improve.
Evidence Supporting Early Initiation
The evidence from the American College of Physicians 1 supports the use of Paxlovid in the outpatient setting for symptomatic patients with confirmed mild to moderate COVID-19 who are within 5 days of the onset of symptoms and at a high risk for progressing to severe disease. This recommendation is based on the living, rapid practice points from the American College of Physicians, which provides guidance on the outpatient treatment of confirmed COVID-19.
Conclusion Not Needed, Direct Answer Provided Above
From the FDA Drug Label
The 5-day treatment course of PAXLOVID should be initiated as soon as possible after a diagnosis of COVID-19 has been made, and within 5 days of symptom onset even if baseline COVID-19 symptoms are mild
Initiation of Paxlovid treatment should be as soon as possible after a diagnosis of COVID-19 has been made, and within 5 days of symptom onset. 2
From the Research
Timing of Paxlovid Initiation
- Paxlovid (nirmatrelvir/ritonavir) should be initiated as early as possible in patients with acute COVID-19 illness, ideally within 5 days of symptom onset 3, 4.
- Studies have shown that early treatment with Paxlovid can reduce the risk of hospitalization and death among patients with mild to moderate COVID-19 who are at risk for progression to severe disease 5, 6.
- One study found that Paxlovid treatment within 10 days of onset can shorten the disease course of COVID-19 by reducing the viral load 7.
Patient Eligibility
- Paxlovid is indicated for patients with COVID-19 who are at risk for progression to severe disease due to the presence of one or more risk factors 6.
- The treatment is approved for persons aged ≥12 years weighing ≥40 kg 3.
- Patients with certain medical conditions or taking certain medications may need to be cautious when taking Paxlovid due to potential drug interactions 3, 4.
Treatment Duration and Outcomes
- Paxlovid is typically given for 5 days, with two doses taken orally twice daily 3, 4.
- Studies have shown that Paxlovid can reduce the risk of hospitalization and death among patients with COVID-19, with absolute risk reductions of 0.9 percentage points for hospitalization and 0.2 percentage points for death 6.
- Paxlovid has been shown to be effective in reducing severe COVID-19 outcomes, including among vaccinated patients and particularly among older patients 6.