PAXLOVID 4 Dosage And Administration

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PAXLOVID is nirmatrelvir tablets co-packaged with ritonavir tablets. Nirmatrelvir must be co-administered with ritonavir. Failure to correctly co-administer nirmatrelvir with ritonavir will result in plasma levels of nirmatrelvir that will be insufficient to achieve the desired therapeutic effect.

The dosage for PAXLOVID is 300 mg nirmatrelvir (two 150 mg tablets) with 100 mg ritonavir (one 100 mg tablet) with all three tablets taken together orally twice daily for 5 days.  Patients should be advised to complete the full 5-day treatment course.

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. Should a patient require hospitalization due to severe or critical COVID-19 after starting treatment with PAXLOVID, the patient should complete the full 5-day treatment course per the healthcare professional’s discretion.

The following medical conditions or other factors place patients at high risk for progression to severe COVID-19:

  • Older age (e., 60 years of age and older)
  • Obesity or being overweight (e., body mass index [BMI] >25 kg/m2)
  • Current smoker
  • Chronic kidney disease
  • Diabetes
  • Immunosuppressive disease or immunosuppressive treatment
  • Cardiovascular disease (including congenital heart disease) or hypertension
  • Chronic lung disease (i.e., chronic obstructive pulmonary disease, asthma [moderate-to-severe], interstitial lung disease, cystic fibrosis, and pulmonary hypertension)
  • Sickle cell disease
  • Neurodevelopmental disorders (e., cerebral palsy, Down’s syndrome) or other conditions that confer medical complexity (i.e., genetic or metabolic syndromes and severe congenital anomalies)
  • Active cancer
  • Medical-related technological dependence not related to COVID-19 (e., tracheostomy, gastrostomy, or positive pressure ventilation)

Other medical conditions or factors (i.e., race or ethnicity) may also place individual patients at high risk for progression to severe COVID-19 and is not limited to the medical conditions or factors listed above.

4.1 Dosing Considerations

  • Concomitant Therapy with Ritonavir or Cobicistat-Containing Regimen

    No dosage adjustment is required when co-administered with other products containing ritonavir or cobicistat. Patients on ritonavir- or cobicistat-containing HIV or HCV regimen should continue their treatment as indicated.

  • Drug-drug Interactions

    Consider the potential for drug interactions prior to and during PAXLOVID therapy and review concomitant medications during PAXLOVID therapy (see 2 CONTRAINDICATIONS, 7 WARNINGS AND PRECAUTIONS, and 9 DRUG INTERACTIONS).

4.2 Recommended Dose and Dosage Adjustment

Recommended Dose:

The recommended dosage for PAXLOVID is 300 mg nirmatrelvir (two 150 mg tablets) with 100 mg ritonavir (one 100 mg tablet) with all three tablets taken together orally twice daily for 5 days. PAXLOVID should be given as soon as possible after positive results of direct SARS-CoV-2 viral testing and within 5 days of symptom onset (see 10 CLINICAL PHARMACOLOGY, 10.3 Pharmacokinetics).

Patients with Renal Impairment:

Systemic exposure of nirmatrelvir increases in renally impaired patients with increase in the severity of renal impairment (see 10 CLINICAL PHARMACOLOGY, 10.3 Pharmacokinetics, Special Populations and Conditions). No dosage adjustment is needed in patients with mild renal impairment (eGFR 60 to <90 mL/min).               

In patients with moderate renal impairment (eGFR ≥30 to <60 mL/min), reduce the dosage of PAXLOVID to 150 mg of nirmatrelvir (one 150 mg tablet) and 100 mg ritonavir (one 100 mg tablet) twice daily for 5 days.  Healthcare professionals should counsel patients about renal dosing instructions (see 6 DOSAGE FORMS, STRENGTHS, COMPOSITION AND PACKAGING, and 10 CLINICAL PHARMACOLOGY, 10.3 Pharmacokinetics).  

PAXLOVID is not recommended in patients with severe renal impairment (eGFR <30 mL/min). 

Patients with Hepatic Impairment:

No dosage adjustment is needed in patients with mild (Child-Pugh Class A) or moderate (Child-Pugh Class B) hepatic impairment. 

No pharmacokinetic or safety data are available regarding the use of nirmatrelvir or ritonavir in subjects with severe hepatic impairment (Child-Pugh Class C); therefore, PAXLOVID is not recommended for use in patients with severe hepatic impairment (see 7 WARNINGS AND PRECAUTIONS, Hepatic/Biliary/Pancreatic).

4.4 Administration

PAXLOVID (both nirmatrelvir; ritonavir tablets) can be taken orally with or without food. The tablets should be swallowed whole and not chewed, broken, or crushed.

4.5 Missed Dose

If the patient misses a dose of PAXLOVID within 8 hours of the time it is usually taken, the patient should take it as soon as possible and resume the normal dosing schedule. If the patient misses a dose by more than 8 hours, the patient should not take the missed dose and instead take the next dose at the regularly scheduled time. The patient should not double the dose to make up for a missed dose.