In this episode, we review Paxlovid (nirmatrelvir/ritonavir) from the perspective of its pharmacology, efficacy, safety, pharmacists’ authority to prescribe, drug interactions, and rebound symptoms after Paxlovid therapy.

Key Concepts

1. Paxlovid is the preferred outpatient therapy for COVID-19 in patients at high risk for progressing to severe COVID-19. It likely has similar efficacy to IV monoclonal antibodies and IV outpatient remdesivir but differences in vaccination rates and patient populations makes a direct comparison difficult.
2. The 5-day course of Paxlovid is generally well tolerated. “Paxlovid mouth” (dysgeusia) is relatively common and is characterized by a terrible metallic or garbage-like taste in the mouth during therapy.
3. As of July 2022, licensed pharmacists have the authority to assess patients for Paxlovid and prescribe the therapy; however, Medicare/Medicaid reimbursement has not clearly established how reimbursement of clinical services can occur.
4. “Rebound” COVID-19 symptoms may or may not be due to Paxlovid (versus the natural course of the disease). If rebound symptoms occur, they are almost always mild or asymptomatic in nature and do not require additional treatment.

References

• DailyMed - PAXLOVID- nirmatrelvir and ritonavir kit (nih.gov). https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=7bdddfba-bd31-44cb-ba9e-23a4e17a4691
• Underlying Medical Conditions Associated with Higher Risk for Severe COVID-19: Information for Healthcare Professionals. CDC. June 15, 2022. https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-care/underlyingconditions.html
• EPIC-HR Study: Hammond J, Leister-Tebbe H, Gardner A, et al. Oral Nirmatrelvir for High-Risk, Nonhospitalized Adults with Covid-19. N Engl J Med. 2022;386(15):1397-1408. doi:10.1056/NEJMoa2118542. https://www.nejm.org/doi/full/10.1056/NEJMoa2118542
• COVID-19 Rebound After Paxlovid Treatment. CDC Health Alert Network. May 24, 2022. https://emergency.cdc.gov/han/2022/han00467.asp
• FDA Authorizes Pharmacists to Prescribe Paxlovid with Certain Limitations. Administration for Strategic Preparedness & Response (ASPR). July 6, 2022. https://aspr.hhs.gov/COVID-19/Therapeutics/updates/Pages/important-update-06July2022.aspx
• PAXLOVID Patient Eligibility Screening Checklist Tool for Prescribers. https://www.fda.gov/media/158165/download