Risk-Benefit Profile of Direct-Acting Oral Anticoagulants in Established Therapeutic Indications: An Overview of Systematic Reviews and Observational Studies

Abstract

Since 2008, the direct-acting oral anticoagulants (DOACs) have expanded the therapeutic options of cardiovascular diseases with recognized clinical and epidemiological impact, such as non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE), and also in the preventive setting of orthopedic surgical patients. The large body of evidence, not only from pivotal clinical trials but also from 'real-world' postmarketing observational findings (e.g. analytical epidemiological studies and registry data) gathered to date allow for a first attempt at verifying a posteriori whether or not the pharmacological advantages of the DOACs actually translate into therapeutic innovation, with relevant implications for clinicians, regulators and patients. This review aims to synthesize the risk-benefit profile of DOACs in the aforementioned consolidated indications through an 'evidence summary' approach gathering the existent evidence-based data, particularly systematic reviews with meta-analyses of randomized controlled trials, as well as observational studies, comparing DOACs with vitamin K antagonists. Clinical evidence will be discussed and compared with major international guidelines to identify whether an update is needed. Controversial clinically relevant safety issues will be also examined in order to highlight current challenges and unsettled questions (e.g. actual bleeding risk in susceptible populations). It is anticipated that the large number of publications on NVAF or VTE (44 systematic reviews with meta-analyses and 12 observational studies retained in our analysis) suggests the potential existence of overlapping studies and calls for common criteria to qualitatively and quantitatively assess discordances, thus guiding future research.

Fig. 1

Simplified approach to guide selection among oral anticoagulants. Asterisk If HAS-BLED ≥3, offer regular monitoring and amend risk factors for bleeding in any patients initiating OACs. Hash In patients with AF undergoing electrical cardioversion, VKAs remain the standard of care, although available data suggest that DOACs may be as safe and as effective. In patients undergoing catheter ablation, uninterrupted warfarin is preferred in many institutions [85, 86]. Double dragger For eligibility of DOACs in specific valvular indications, please refer to the ESC guidelines [82]. Dragger Dose adjustment required, especially in patients aged >80 years, body weight <60 kg, creatinine >1.5 mg/dl. For all DOACs, please refer to the relevant summary of product characteristics or product information to verify whether or not dose adjustment is needed, including the extent of renal impairment and concomitant use of P-glycoprotein inhibitors and/or CYP3A4 inhibitors. A apixaban, D110 dabigatran 110 mg, DOAC direct-acting oral anticoagulant, E edoxaban, OAC oral anticoagulant, R rivaroxaban, TTR time in therapeutic range, VKA vitamin K antagonist, ClCr creatinine clearance, GI gastrointestinal, ACS acute coronary syndrome, AF atrial fibrillation, ESC European Society of Cardiology, CYP cytochrome P450