REVERXaL study aims to increase the understanding of the patient characteristics, bleeding presentation, health care interventions provided, and the clinical as well as self-reported health outcomes of patients with major bleeding in the presence of Factor Xa inhibitor treatment. The generation of insight on treatment approaches and associated outcomes in hospitalized patients with Factor Xa inhibitor-related major bleeds may inform clinical guidelines, health system decision making and streamline treatment pathways in this population.

REVERXaL is a multinational observational study incorporating 2 patient cohorts (historical and prospective) with major bleeds during Factor Xa inhibitor use. This study will be mainly descriptive in nature without any pre-specified statistical hypotheses. Variables will be collected according to routine medical practice either through primary data collection directly from patients, or from secondary data collection via data extraction from electronic or paper medical records into electronic case report forms (eCRFs). Patients will undergo clinical assessments and receive standard medical care as determined by their treating physicians. Patients will not receive any experimental disease management intervention or experimental treatment because of their participation in the study. As part of routine care, study investigators will evaluate patients about their medical history, medication history, bleeding presentation, and any adverse event (AE) or severe adverse event (SAE) experiences since the previous clinical visit and the related information. No additional or pre-defined site visits will be scheduled outside of the patient's routine clinical visits.

Inclusion Criteria:

• Aged ≥18 years on the index date
• Admitted to the hospital with an acute major bleeding or developed an acute bleeding while already in hospital
• Ongoing treatment with a Factor Xa inhibitor before the index date
• Provided signed and dated informed consent or able to obtain a waiver

In addition, for cohort B:

- Administered reversal or replacement therapy

Exclusion Criteria:

• Pregnant women
• Patients enrolled in any interventional trial that includes reversal/replacement agents

In addition, for cohort B:

• Use of vitamin K antagonists, dabigatran, prothrombin complex concentrates or recombinant factor VII, or transfusion of whole blood or plasma within the preceding 7 days of the index event
• As judged by the investigator, if it is deemed undesirable for the patient to participate in the study or participant is unlikely to comply with study procedures, and requirements
• Involvement in the planning and/or conduct of the study (applies to both AstraZeneca staff and/or staff at the study site)

All patients aged ≥18 years admitted to hospital with an acute major bleeding or developed an acute bleeding while already in hospital and received ongoing treatment with a Factor Xa inhibitor before the index date.

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

"Yes", indicates that AZ are accepting requests for IPD, but this does not mean all requests will be approved.

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA/PhRMA Data-Sharing Principles. For details of our timelines, please refer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org. A Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.