Disposition of Nirmatrelvir, an Orally Bioavailable Inhibitor of SARS-CoV-2 3C-Like Protease, across Animals and Humans

Copyright © 2022 by The American Society for Pharmacology and Experimental Therapeutics..

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 3C-like protease inhibitor PF-07321332 (nirmatrelvir), in combination with ritonavir (Paxlovid), was recently granted emergency use authorization by multiple regulatory agencies for the treatment of coronavirus disease 2019 (COVID-19) in adults and pediatric patients. Disposition studies on nirmatrelvir in animals and in human reagents, which were used to support clinical studies, are described herein. Plasma clearance was moderate in rats (27.2 ml/min per kg) and monkeys (17.1 ml/min per kg), resulting in half-lives of 5.1 and 0.8 hours, respectively. The corresponding oral bioavailability was moderate in rats (34%-50%) and low in monkeys (8.5%), primarily due to oxidative metabolism along the gastrointestinal tract in this species. Nirmatrelvir demonstrated moderate plasma protein binding in rats, monkeys, and humans with mean unbound fractions ranging from 0.310 to 0.478. The metabolism of nirmatrelvir was qualitatively similar in liver microsomes and hepatocytes from rats, monkeys, and humans; prominent metabolites arose via cytochrome P450 (CYP450)-mediated oxidations on the P1 pyrrolidinone ring, P2 6,6-dimethyl-3-azabicyclo[3.1.0]hexane, and the tertiary-butyl group at the P3 position. Reaction phenotyping studies in human liver microsomes revealed that CYP3A4 was primarily responsible (fraction metabolized = 0.99) for the oxidative metabolism of nirmatrelvir. Minor clearance mechanisms involving renal and biliary excretion of unchanged nirmatrelvir were also noted in animals and in sandwich-cultured human hepatocytes. Nirmatrelvir was a reversible and time-dependent inhibitor as well as inducer of CYP3A activity in vitro. First-in-human pharmacokinetic studies have demonstrated a considerable boost in the oral systemic exposure of nirmatrelvir upon coadministration with the CYP3A4 inhibitor ritonavir, consistent with the predominant role of CYP3A4 in nirmatrelvir metabolism. SIGNIFICANCE STATEMENT: The manuscript describes the preclinical disposition, metabolism, and drug-drug interaction potential of PF-07321332 (nirmatrelvir), an orally active peptidomimetic-based inhibitor of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 3CL protease, which has been granted emergency use authorization by multiple regulatory agencies around the globe for the treatment of coronavirus disease 2019 (COVID-19) in COVID-19-positive adults and pediatric patients who are at high risk for progression to severe COVID-19, including hospitalization or death.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:50

Enthalten in:

Drug metabolism and disposition: the biological fate of chemicals - 50(2022), 5 vom: 13. Mai, Seite 576-590

Sprache:

Englisch

Beteiligte Personen:

Eng, Heather [VerfasserIn]
Dantonio, Alyssa L [VerfasserIn]
Kadar, Eugene P [VerfasserIn]
Obach, R Scott [VerfasserIn]
Di, Li [VerfasserIn]
Lin, Jian [VerfasserIn]
Patel, Nandini C [VerfasserIn]
Boras, Britton [VerfasserIn]
Walker, Gregory S [VerfasserIn]
Novak, Jonathan J [VerfasserIn]
Kimoto, Emi [VerfasserIn]
Singh, Ravi Shankar P [VerfasserIn]
Kalgutkar, Amit S [VerfasserIn]

Links:

Volltext

Themen:

7R9A5P7H32
9DLQ4CIU6V
Cytochrome P-450 CYP3A
EC 1.14.14.1
EC 3.4.-
GMW67QNF9C
Journal Article
Lactams
Leucine
Nirmatrelvir
Nitriles
O3J8G9O825
Peptide Hydrolases
Proline
Ritonavir

Anmerkungen:

Date Completed 03.05.2022

Date Revised 07.12.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1124/dmd.121.000801

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM336853130