Pharmacokinetic Interactions of Paxlovid Involving CYP3A Enzymes and P-gp Transporter: An Overview of Clinical Data

Background: The US FDA has approved paxlovid, a combination of nirmatrelvir and ritonavir, as the first oral treatment for the management of mild-to-moderate COVID-19 patients. Objective: The purpose of this review article is to explore the clinical data that is currently available regarding the drug-drug interactions (DDIs) of paxlovid with various medications. Methods: Keywords, such as drug interactions, paxlovid, ritonavir, nirmatrelvir, pharmacokinetic interactions, CYP3A, and P-glycoprotein, were used to search online databases, including LitCOVID, Scopus, Embase, EBSCO host, Google Scholar, ScienceDirect, Cochrane Library, and reference lists. Results: Paxlovid interacted with a variety of medications due to strong inhibition of CYP3A4 and P-gp transporter protein by ritonavir and the dual function of nirmatrelvir as a substrate and inhibitor of CYP3A enzymes and P-gp transporter protein. Numerous case reports and other studies determined that the risk of toxicities of several drugs, including anticoagulants (warfarin, rivaroxaban), calcium channel blockers (nifedipine, manidipine, verapamil), statins (atorvastatin), immunosuppressants (tacrolimus), antiarrhythmics (amiodarone), antipsychotics (clozapine, quetiapine), and ranolazine have been enhanced by the concomitant administration of paxlovid. Conclusion: Adverse effects of paxlovid from DDIs can range from less-than-ideal therapeutic responses to potentially fatal toxicities. Effective management requires close observation, adjustments to dosage, and assessment of substitute treatments. Collaboration between pharmacists and other medical professionals is necessary to guarantee effective and safe treatment outcomes of paxlovid therapy.