Non-vitamin K Antagonist Oral Anticoagulants (NOACs) Versus Warfarin in Patients with Atrial Fibrillation Using P-gp and/or CYP450-Interacting Drugs: a Systematic Review and Meta-analysis.

PURPOSE: Non-vitamin K antagonist oral anticoagulants (NOACs) are excreted by P-glycoprotein (P-gp) and some are metabolized by CYP450 enzymes such as CYP3A4. Although fewer drug interactions are present with NOACs, it is unclear whether NOACs should also be preferred over vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) using pharmacokinetically interacting drugs. Therefore, the benefit-risk profile of NOACs versus VKAs was investigated in AF patients treated with P-gp and/or CYP450-interacting drugs. METHODS: Using PubMed and Embase, randomized controlled trials and observational studies on the effectiveness and safety of NOACs versus VKAs in AF patients using P-gp and/or CYP450-interacting drugs were included. A meta-analysis was performed, calculating relative risks (RR) and 95% confidence intervals (CI) with the Mantel-Haenszel method. RESULTS: Twelve studies were included, investigating 10,793 NOAC and 10,096 VKA users treated with P-gp/CYP3A4 inhibitors, whereas no studies on P-gp and/or CYP450-inducing drugs were identified. Compared to VKAs, NOACs were associated with a borderline non-significantly lower stroke or systemic embolism (stroke/SE) risk (RR 0.85, 95%CI (0.72-1.01)), significantly lower intracranial bleeding (RR 0.47, 95%CI (0.34-0.65)) and all-cause mortality risks (RR 0.87, 95%CI (0.79-0.95), but significantly higher gastrointestinal bleeding risk (RR 1.74, 95%CI (1.06-2.86)). Among AF patients using amiodarone, NOACs were associated with significantly lower stroke/SE (RR 0.71, 95%CI (0.54-0.93)) and intracranial bleeding risks (RR 0.51, 95%CI (0.29-0.88)), but significantly higher gastrointestinal bleeding risk (RR 2.15, 95%CI (1.24-3.72)) than VKAs. CONCLUSION: The benefit-risk profile of NOACs compared to VKAs was preserved in AF patients using P-gp/CYP3A4 inhibitors, including amiodarone.

Impact of P-glycoprotein and/or CYP3A4-interacting drugs on effectiveness and safety of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: A meta-analysis.

AIMS: P-glycoprotein (P-gp) and CYP3A4-interacting drugs influence plasma levels of non-vitamin K antagonist oral anticoagulants (NOACs). However, the clinical relevance is questioned. Therefore, the impact of pharmacokinetically-interacting drugs on the effectiveness and safety of NOACs in patients with atrial fibrillation (AF) was investigated. METHODS: A meta-analysis was performed based on randomized controlled trials and observational studies retrieved from Pubmed and Embase that investigated the impact of concomitantly used P-gp/CYP3A4-interacting drugs on the risk-benefit profile of NOACs in AF patients. RESULTS: Fifteen studies were included, investigating 21 711 and 306 421 NOAC-treated AF patients with and without P-gp/CYP3A4 inhibitor use respectively, while only 1 study included P-gp/CYP3A4 inducers. In NOAC-treated AF patients, concomitant use of P-gp/CYP3A4 inhibitors was associated with significantly higher major bleeding (relative risk [RR] 1.10, 95% confidence interval [CI; 1.01-1.19]) and all-cause mortality risks (RR 1.14, 95%CI [1.05-1.23]) compared to not using P-gp/CYP3A4 inhibitors, while the risks of stroke/systemic embolism (RR 0.88, 95%CI [0.77-1.01]), intracranial bleeding (RR 0.89, 95%CI [0.68-1.15]) and gastrointestinal bleeding (RR 1.09, 95%CI [0.91-1.30]) were not significantly different. Concomitant use of amiodarone with NOACs was associated with lower thromboembolic (RR 0.75, 95%CI [0.61-0.92]), similar major bleeding (RR 0.92, 95%CI [0.80-1.07]) but higher mortality risks (RR 1.21, 95%CI [1.05-1.39]). Coadministration of verapamil or diltiazem was associated with higher major bleeding risks (RR 1.64, 95%CI [1.31-2.06]), but comparable thromboembolic (RR 1.10, 95%CI [0.75-1.61]) and mortality risks (RR 1.01, 95%CI [0.77-1.33]). CONCLUSION: Given the higher bleeding and mortality risks in NOAC-treated AF patients concomitantly using P-gp/CYP3A4 inhibitors, close monitoring is warranted.