Edoxaban Exposure in Patients With Atrial Fibrillation and Estimated Creatinine Clearance Exceeding 100 mL/min

Can edoxaban be used at extremes of bodyweight and in patients with a creatinine clearance ≥95 ml/min? - A population pharmacokinetic analysis

BACKGROUND

Clinical evidence surrounding edoxaban use in patients weighing <50 kg and >120 kg is lacking. The International Society of Thrombosis and Haemostasis Scientific and Standardisation Committee suggests avoiding edoxaban in patients >120 kg. Additionally, concerns exist regarding decreased efficacy in patients prescribed edoxaban for atrial fibrillation with a creatinine clearance (CrCl) >95 ml/min, a finding of the ENGAGE AF-TIMI 48 trial when edoxaban was compared to warfarin.

OBJECTIVE

To derive a population pharmacokinetic (PopPK) model using clinical practice data, to understand the impact of bodyweight and renal function on edoxaban pharmacokinetics.

METHOD

Edoxaban plasma concentrations and patient characteristics were collated from King's College Hospital anticoagulation clinics between 11/2016 and 08/2022. A PopPK model was developed using non-linear mixed effects modelling and used to simulate edoxaban concentrations at the extremes of bodyweight and with varying renal function.

RESULTS

Data from 409 patients (46 < 50 kg, 34 > 120 kg and 123 with a CrCl > 95 ml/min) provided 455 edoxaban plasma concentrations. A one-compartment model with between-subject variability on clearance with a proportional error model best described the data. The most significant covariates impacting on edoxaban exposure were CrCl and bodyweight. Our work suggests that edoxaban exposure in patients weighing up to 140 kg is comparable to those weighing 75 kg. Edoxaban exposure is reduced in patients weighing <50 kg due to the recommended dose reductions. There is also a reduction in AUCss when CrCl > 95 ml/min compared to CrCl 80 ml/min.

CONCLUSIONS

Our population PK model for edoxaban suggests that renal function is a key driver for overall edoxaban exposure. Further clinical outcome data is required to understand clinical effectiveness and adverse outcomes.

Impact of increased kidney function on clinical and biological outcomes in real-world patients treated with Direct Oral Anticoagulants

BACKGROUND AND PURPOSE

Renal excretion of direct oral anticoagulants (DOACs) varies depending on the drug. Hypothetically, an increased glomerular filtration rate (GFR) may lead to suboptimal dosing and a higher thromboembolic events incidence. However, real-world patient data do not support the theoretical risk. The aim is to analyse DOAC outcomes in patients with normal and high (≥90 mL/min) GFR, focusing on biological parameters and thrombotic/haemorrhagic events.

METHODS

Observational prospective single-centre study and registry of patients on DOACs. Follow-up was 1,343 patient-years. A bivariate analysis was performed of baseline variables according to GFR (<90 mL/min vs ≥90 mL/min). Anti-Xa activity before and after drug intake (HemosIL, Liquid Anti-Xa, Werfen) was measured for edoxaban, apixaban, and rivaroxaban; diluted thrombin time for dabigatran (HEMOCLOT); and additionally, plasma concentrations in edoxaban (HemosIl, Liquid Anti-Xa suitably calibrated).

RESULTS

1,135 patients anticoagulated with DOACs were included and 152 patients with GFR ≥90 mL/min. Of 18 serious thrombotic complications during follow-up, 17 occurred in patients with GFR <90 mL/min, and 1 in a patient with GFR ≥90 mL/min. A higher incidence of complications was observed in patients with normal GFR, but the difference was not statistically significant (p>0.05). No statistically significant differences with clinical relevance were observed between the normal or supranormal groups in anti-Xa activity or in edoxaban plasma concentrations.

CONCLUSIONS

There was no increased incidence of thrombotic/haemorrhagic complications in our patients treated with DOACs, including 66% treated with edoxaban, and patients with GFR ≥90 mL/min. Likewise, drug anti-Xa activity and edoxaban plasma concentration did not seem to be influenced by GFR.

The non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients with high-normal renal function - A systematic review

Non-vitamin K antagonist oral anticoagulants (NOACs) have revolutionized treatment of atrial fibrillation. Although benefits of anticoagulation therapy are clear, a minority of patients still experience treatment inefficacy or harm. All NOACs have varying degree of renal clearance, which may significantly affect plasma concentrations. Pivotal clinical trials have explored the effects of dose reduction in patients with chronic renal disease. None of these have, however, specifically addressed the need for a dose up-titration in patients with renal hyperfiltration, in whom lower drug plasma levels are to be expected. A signal for lower efficacy in this patient subset has recently emerged. We systematically assessed the peer-reviewed scientific literature on this topic, including a recently reported randomized pharmacokinetic study in renal hyperfiltrators also reporting on ischemic and bleeding events. We conclude that the reduction in NOAC plasma levels in AF patients with renal hyperfiltration is limited in extent and, does not translate into a clinically meaningful reduction in efficacy for NOACs as compared to vitamin K antagonists (VKAs) in such patients. At the current state of knowledge, NOAC current dosing should not be altered in patients with high-normal renal function.