Dosing recommendation of nirmatrelvir/ritonavir using an integrated population pharmacokinetic analysis

© 2023 Pfizer Inc. CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics..

Protease inhibitor nirmatrelvir coadministered with ritonavir as a pharmacokinetic enhancer (PAXLOVID™; Pfizer Inc) became the first orally bioavailable antiviral agent granted Emergency Use Authorization in the United States in patients ≥12 years old with mild to moderate coronavirus disease 2019 (COVID-19). This population pharmacokinetic analysis used pooled plasma nirmatrelvir concentrations from eight completed phase I and II/III studies to characterize nirmatrelvir pharmacokinetics when coadministered with ritonavir in adults with/without COVID-19. Influence of covariates (e.g., formulation, dose, COVID-19) was examined using a stepwise forward selection (α = 0.05) and backward elimination (α = 0.001) approach. Simulations with 5000 subjects for each age and weight group and renal function category were performed to support dosing recommendations of nirmatrelvir/ritonavir for adults with COVID-19 and guide dose adjustments for specific patient populations (e.g., renal insufficiency, pediatrics). The final model was a two-compartment model with first-order absorption, including allometric scaling of body weight and dose-dependent absorption (power function on relative bioavailability). Nirmatrelvir clearance (CL) increased proportionally to body surface area-normalized creatinine CL (nCLCR) up to 70 ml/min/1.73 m2 and was independent of nCLCR above the breakpoint. Significant covariates included carbamazepine or itraconazole coadministration as markers for drug interactions, COVID-19 on CL, formulation on relative bioavailability, and age on central volume of distribution. Simulation results support current dosing recommendations of nirmatrelvir/ritonavir 300/100 mg twice daily (b.i.d.) in adults with normal renal function or mild impairment and pediatrics (12 to <18 years) weighing ≥40 kg and nirmatrelvir/ritonavir 150/100 mg b.i.d. in adults with moderate renal impairment.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:12

Enthalten in:

CPT: pharmacometrics & systems pharmacology - 12(2023), 12 vom: 15. Dez., Seite 1897-1910

Sprache:

Englisch

Beteiligte Personen:

Chan, Phylinda L S [VerfasserIn]
Singh, Ravi Shankar P [VerfasserIn]
Cox, Donna S [VerfasserIn]
Shi, Haihong [VerfasserIn]
Damle, Bharat [VerfasserIn]
Nicholas, Timothy [VerfasserIn]

Links:

Volltext

Themen:

12794-10-4
Antiviral Agents
Benzodiazepines
Journal Article
O3J8G9O825
Ritonavir

Anmerkungen:

Date Completed 18.12.2023

Date Revised 18.12.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/psp4.13039

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM362974667