TARGET-EU: Rivaroxaban and risk of major gastrointestinal bleeding in elderly patients with non-valvular atrial fibrillation

29/05/2026
29/05/2026
EU PAS number:
EUPAS1000001001
Study
Planned
Study summary
No information provided.
Study identification

EU PAS number

EUPAS1000001001

Study ID

1000001001

Official title and acronym

TARGET-EU: Rivaroxaban and risk of major gastrointestinal bleeding in elderly patients with non-valvular atrial fibrillation

DARWIN EU® study

No

Study countries

Denmark
Netherlands
Spain

Study description

This case study is part of the broader TARGET-EU project (EUPAS1000000539), which aims to advance the regulatory use of real-world data through the application of target trial emulation and estimand methodologies.
Background: Non-valvular atrial fibrillation (NVAF) is a common arrhythmia associated with significant morbidity and mortality. Direct oral anticoagulants (DOACs) are recommended over vitamin K antagonists in NVAF patients. Evidence suggests clinically important differences in bleeding risk between DOACs, particularly in high-risk populations such as the elderly, who are often underrepresented in randomised controlled trials.
Objectives: The primary objective is to estimate the effect of initiating rivaroxaban versus apixaban on time to a first major gastrointestinal (GI) bleeding event among adults aged 75 years or older with non-valvular atrial fibrillation.
Methods: We will conduct an active comparator new-user cohort study using linked electronic health records from Denmark (Danish national registers) and Spain (SIDIAP). Eligible individuals are adults aged 75 years or older who initiated rivaroxaban or apixaban between 2013 and 2023. In the primary analysis, a while-on-treatment strategy is used for treatment-related intercurrent events (discontinuation and switching), and a while-alive strategy is applied to non-GI bleeding death. Inverse probability of treatment weighting (IPTW) is used to estimate treatment effects. The primary analysis uses a Cox proportional hazards model, with supplemental analyses using an accelerated failure time model to estimate restricted mean survival time at 1 and 2 years. Sensitivity analyses will assess the impact of departures from key assumptions, including censoring-at-random (via inverse probability of censoring weighting) and outcome misclassification (via probabilistic bias analysis).

Study status

Planned
Research institutions and networks

Institutions

Teamit Institute
Spain
First published:
12/03/2024
Institution Other ENCePP partner
University of Copenhagen (UCPH)

Contact details

Patrick Souverein

Primary lead investigator

Study timelines

Date when funding contract was signed

Planned:

Study start date

Planned:

Date of final study report

Planned:
Regulatory

Was the study required by a regulatory body?

No

Is the study required by a Risk Management Plan (RMP)?

Not applicable