This site is intended only for all Healthcare Professionals residing in South Africa




Sign InLog Out Our medicinesTherapy areasExplore contentExplore contentEventsDownloadable materialsVideosLet’s connectLet's ConnectContact usPfizer medical information



Dosage Efficacy Interactions Prescribing Information Quality of Life Safety Information Testing and Method of Administration Patient Resource Materials
InteractionsXALKORI® (crizotinib) is a substrate of CYP3A4/5 and also a moderate, time-dependent inhibitor of CYP3A1

XALKORI® (crizotinib) is an inhibitor of CYP2B6 in vitro. XALKORI® (crizotinib) may have the potential to increase plasma concentrations of coadministered medicines that are predominantly metabolised by CYP2B61

Coadministration of crizotinib with medicines that increase gastric pH:1
The aqueous solubility of crizotinib is pH dependent, with low (acidic) pH resulting in higher solubility. Administration of a single 250 mg crizotinib dose following treatment with esomeprazole 40 mg once daily for 5 days resulted in an approximately 10 % decrease in crizotinib total exposure (AUCinf) and no change in peak exposure (Cmax); the extent of the change in total exposure was not clinically meaningful. Therefore, starting dose adjustment is not required when crizotinib is coadministered with medicines that increase gastric pH (such as proton-pump inhibitors, H2 blockers or antacids).

Coadministration of crizotinib and CYP3A substrates1
  • Crizotinib has been identified as an inhibitor of CYP3A both in vitro and in vivo. Following 28 days of crizotinib dosing at 250 mg taken twice daily in cancer patients, the oral midazolam AUC was 3,7-fold (90 % CI: 2,63 - 5,07) those seen when midazolam was administered alone, suggesting that crizotinib is a moderate inhibitor of CYP3A.
Coadministration of crizotinib and CYP3A inhibitors1
  • Coadministration of a single 150 mg oral dose of crizotinib in the presence of ketoconazole (200 mg twice daily), a strong CYP3A inhibitor, resulted in increases in crizotinib systemic exposure, with crizotinib AUCinf and Cmax values that were approximately 3,2-fold and 1,4-fold respectively, those seen when crizotinib was administered alone. However, the magnitude of effect of CYP3A inhibitors on steady-state crizotinib exposure has not been established.
Coadministration of crizotinib and CYP3A inducers1
  • Coadministration of crizotinib (250 mg twice daily) with rifampin (600 mg once daily), a strong CYP3A inducer, resulted in 84 % and 79 % decreases in crizotinib steady-state AUCtau and Cmax, respectively, compared to when crizotinib was given alone.
Coadministration with other CYP substrates:1
  • In vitro studies indicated that clinical drug-drug interactions are unlikely to occur as a result of crizotinib-mediated inhibition of the metabolism of medicines that are substrates for CYP1A2, CYP2C8, CYP2C9, CYP2C19 or CYP2D6. Crizotinib is an inhibitor of CYP2B6 in vitro. Therefore, crizotinib may have the potential to increase plasma concentrations of coadministered medicines that are predominantly metabolised by CYP2B6.
  • In vitro studies in human hepatocytes indicated that clinical interactions are unlikely to occur as a result of crizotinib-mediated induction of the metabolism of medicines that are substrates for CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19 or CYP3A.
References:Pfizer Laboratories (Pty) Ltd. XALKORI® 200 mg and 250 mg capsules Package Insert, approved 20 March 2018.

Copyright ©2023 Pfizer South Africa All rights reserved.

  • The information contained herein is provided for educational purposes only and is not intended to constitute medical advice or replace discussions with a Healthcare Professional. All decisions regarding patient care must be made with a Healthcare Professional, considering the unique characteristics of the patient.
  • While every effort is made to update the information regularly and to offer the most current, correct and clearly expressed information possible, Pfizer cannot be held responsible for any inaccuracy, errors, omissions or misinterpretations.
  • Pfizer, its officers and/or its employees do not accept or take any responsibility whatsoever for any loss, whether direct, indirect or consequential, which may arise from reliance on information contained on these pages and actions resulting therefrom. Any liability that would or could arise as a result of the contents of these pages is hereby excluded to the fullest extent allowed by law.
  • No warranty is given that any files, downloads or applications available via this web site are free of viruses which have the ability to corrupt your system.
  • Any and all information is subject to change without notice.
  • The information provided in this site is intended only for appropriate Healthcare Professionals residing in South Africa.


PfizerPro AccountPfizerPro Account

To access further materials, resources and receive communication about medicines and vaccines promoted by Pfizer.

Sign inRegisterAccountSign Out

This site is intended only for all Healthcare Professionals residing in South Africa. If you are a member of the public wishing to access information on a specific medicine, please visit


This website is brought to you by Pfizer South Africa 

Pfizer Laboratories (Pty) Ltd. Company Reg. No. 1954/000781/07. Building 2, 1st Floor, Maxwell Office Park, Magwa Crescent, Waterfall City, Midrand, Johannesburg, South Africa. Tel. No: 0860 PFIZER (734937).


Copyright © 2023. Pfizer Laboratories (Pty) Ltd. All rights reserved

For South Africa Healthcare Professionals *

These pages are not intended for patients or for members of the general public. The healthcare professional webpages contain promotional content.

I confirm that I am a healthcare professional residing in South Africa. If you select 'No', you will be redirected to where you will be able to access reference information on Pfizer's prescription medicines.

Yes No
You are now leaving the PfizerPro South Africa website
You are leaving the South Africa HCP Portal website and being directed to a new website

This website is not controlled by South Africa HCP portal or subject to our privacy policy.

Thank you for visiting our site. We hope your visit was informative and enjoyable