Effect of the CYP3A inhibitors, diltiazem and ketoconazole, on ticagrelor pharmacokinetics in healthy volunteers

Abstract

Objectives:

Two open-label, two-period, crossover studies in healthy volunteers were designed to determine the pharmacokinetic interactions between ticagrelor, a P2Y₁₂ receptor antagonist, and a moderate (diltiazem) and a strong (ketoconazole) cytochrome P450 (CYP) 3A inhibitor.

Methods:

Seventeen volunteers received diltiazem (240 mg once daily) for 14 days. In the second study, ketoconazole (n = 14) 200 mg twice daily was given for 10 days. A single oral 90-mg ticagrelor dose was administered on day 8 (diltiazem) or day 4 (ketoconazole). In each study, volunteers received a single 90-mg oral dose of ticagrelor before or after washout (≥14 days). Pharmacokinetic parameters for ticagrelor, AR-C124910XX (primary metabolite), diltiazem, and ketoconazole were assessed.

Results:

Compared with ticagrelor alone, diltiazem co-administration significantly increased the mean maximum concentration (C_max) and mean area under the plasma concentration–time curve (AUC) for ticagrelor by 69% and 174%, respectively. Diltiazem co-administration reduced C_max by 38% but had no significant effect on AUC for AR-C124910XX. C_max and AUC for ticagrelor were increased by 135% and 632%, respectively, by ketoconazole co-administration, whereas these parameters were reduced by 89% and 56%, respectively, for AR-C124910XX. Diltiazem and ketoconazole pharmacokinetic parameters were not significantly affected by the presence of ticagrelor.

Conclusions:

These results suggest that ticagrelor can be co-administered with moderate CYP3A inhibitors. However, co-administration of strong CYP3A inhibitors with ticagrelor is not recommended.

Keywords::

• Antiplatelet therapy
• Diltiazem
• Ketoconazole
• Pharmacokinetics
• Ticagrelor

Transparency

Declaration of funding

This study was funded by AstraZeneca.

Declarations of financial relationships

All of the authors are employees of AstraZeneca.

R.T. is a member of the American College of Clinical Pharmacology. K.B. is a member of the American Society of Clinical Pharmacology and Therapeutics.

Acknowledgments

The authors thank the Principal Investigators, Dr K. Lasseter (SFBC International, Miami, FL, USA; diltiazem study) and Dr D. Hoelscher (PPD Development Inc., West Austin, TX, USA) and their teams. Colleagues at Clinical Pharmacology & DMPK including Helen Winter (Pharmacokineticist), and those at York Bioanalytical Solutions are acknowledged for their contribution to the pharmacokinetic analyses. Statistical support was provided by Patrick Mitchell and Jennifer Hamer-Maansson (both employees of AstraZeneca). We also thank Jackie Phillipson (Gardiner-Caldwell Communications) who provided medical writing support funded by AstraZeneca.