Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 4INTERVENTIONAL

The Danish Warfarin-Dialysis Study - Safety and Efficacy of Warfarin in Patients With Atrial Fibrillation on Dialysis

Q: Who can participate in NCT03862859?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

Q: How do I contact the trial site for NCT03862859?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Q: Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Q: Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

The Danish Warfarin-Dialysis Study: Safety and Efficacy of Warfarin in Patients With Atrial Fibrillation on Dialysis - A Nationwide Parallel-group Open Randomized Clinical Trial

The Danish Warfarin-Dialysis Study - Safety and Efficacy of Warfarin in Patients With Atrial Fibrillation on Dialysis (NCT03862859) is a Phase 4 interventional studying Atrial Fibrillation and Flutter and Stroke, sponsored by Nicholas Carlson. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

The study aims to evaluate the appropriateness of initiating oral anticoagulation for stroke risk reduction in dialysis populations with atrial fibrillation. Specifically, the study will assess the overall safety, tolerability, and efficacy of initiating treatment with Warfarin in patients with end-stage renal disease on dialysis and atrial fibrillation.

What Stage of Research Is This?

Phase 4 studies happen after a treatment has been approved by the FDA. They monitor long-term safety, real-world effectiveness, and any rare side effects that only emerge in larger populations over longer periods. Phase 4 results sometimes lead to label changes, additional warnings, or — rarely — withdrawal of approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

A target enrollment of 718 participants makes this a sizable late-stage trial. Studies in this range typically have enough power to detect clinically meaningful differences from a comparator and to characterize less-common side effects.

Who May Be Eligible (Plain English)

Who May Qualify: - Patients ≥18 years on chronic dialysis due to end-stage renal disease - Non-valvular paroxysmal, persistent, or permanent atrial fibrillation OR non-treated (for \>2 months) prevalent paroxysmal, persistent or permanent atrial fibrillation as documented by an electrocardiogram or an episode of ≥30 seconds on Holter monitor, or episodes ≥ 6 minutes on event recorders or any other recording device. - Competence to understand the study rationale, including potential risks and benefits associated with treatment, necessary for written willing to sign a consent form. Who Should NOT Join This Trial: - CHA2DS2-VASc Score ≤1 - Other indications for oral anticoagulation treatment (pulmonary embolism \< 6 months, deep vein thrombosis \<3 months, mechanical heart valve prosthesis) irrespective of whether treatment is implemented - Ongoing dual antiplatelet treatment - Malignancy (with exception of non-melanoma skin cancer) with recent \< 1 year, ongoing, or planned curative, or palliative chemo- , radiation-, and/or scheduled surgical therapy - Endoscopy with gastrointestinal ulcer \<1 month - Esophageal varices - Autoimmune og genetic coagulation disorders - Congenital alactasia, Lapp Lactase deficiency or glucose-galactose malabsorption - Pending spinal tap - Cerebrovascular malformations - Arterial aneurysms - Ulcers or wounds (Wagner grad \>1) - Bacterial endocarditis \< 3 months - Active bleeding contraindicating anticoagulation - Any non-elective and/or non-ambulant surgery \<7 days - Cerebral hemorrhage \<4 weeks - Thrombocytopenia (platelet count \<100 × 109/L) \<30 days. - Severe liver insufficiency (spontaneous international normalized ratio \>1.5) \<30 days. - Known intolerance to warfarin - Use of hypericum perforatum / St. John's Wort - Uncontrolled hypertension (repeat blood pressure \>180/110 mmhg) \< 30 days - Uncontrolled hyperthyroidism (thyroid-stimulating hormone \<0.1μIU/mL) \<30 days - Pregnancy or lactation ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Patients ≥18 years on chronic dialysis due to end-stage renal disease * Non-valvular paroxysmal, persistent, or permanent atrial fibrillation OR non-treated (for \>2 months) prevalent paroxysmal, persistent or permanent atrial fibrillation as documented by an electrocardiogram or an episode of ≥30 seconds on Holter monitor, or episodes ≥ 6 minutes on event recorders or any other recording device. * Competence to understand the study rationale, including potential risks and benefits associated with treatment, necessary for written informed consent. Exclusion Criteria: * CHA2DS2-VASc Score ≤1 * Other indications for oral anticoagulation treatment (pulmonary embolism \< 6 months, deep vein thrombosis \<3 months, mechanical heart valve prosthesis) irrespective of whether treatment is implemented * Ongoing dual antiplatelet treatment * Malignancy (with exception of non-melanoma skin cancer) with recent \< 1 year, ongoing, or planned curative, or palliative chemo- , radiation-, and/or scheduled surgical therapy * Endoscopy with gastrointestinal ulcer \<1 month * Esophageal varices * Autoimmune og genetic coagulation disorders * Congenital alactasia, Lapp Lactase deficiency or glucose-galactose malabsorption * Pending spinal tap * Cerebrovascular malformations * Arterial aneurysms * Ulcers or wounds (Wagner grad \>1) * Bacterial endocarditis \< 3 months * Active bleeding contraindicating anticoagulation * Any non-elective and/or non-ambulant surgery \<7 days * Cerebral hemorrhage \<4 weeks * Thrombocytopenia (platelet count \<100 × 109/L) \<30 days. * Severe liver insufficiency (spontaneous international normalized ratio \>1.5) \<30 days. * Known intolerance to warfarin * Use of hypericum perforatum / St. John's Wort * Uncontrolled hypertension (repeat blood pressure \>180/110 mmhg) \< 30 days * Uncontrolled hyperthyroidism (thyroid-stimulating hormone \<0.1μIU/mL) \<30 days * Pregnancy or lactation * Participation in other ongoing intervention trials adjudged to influence study outcomes

Treatments Being Tested

DRUG

Warfarin

Dose adjusted Warfarin targeting an international normalized ratio of 2-3.

Locations (13)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Aalborg University Hosptial

Aalborg, Denmark

Aarhus University Hospital

Aarhus, Denmark

Department of Nephrology, Copenhagen University Hospital Rigshospitalet

Copenhagen, Denmark

Esbjerg and Grindsted Hospital

Esbjerg, Denmark

Department of Nephrology, Herlev Hospital

Herlev, Denmark

Department of nephrology, Nordsjaellands Hospital

Hillerød, Denmark

Holbaek Hospital

Holbæk, Denmark

Holstebro Hospital

Holstebro, Denmark

Lillebælt Hospital

Kolding, Denmark

Zealand University Hospital

Roskilde, Denmark

Bornholms Hospital

Rønne, Denmark

Hospital Sønderjylland

Sønderborg, Denmark

Viborg Regional Hospital

Viborg, Denmark

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT03862859), the sponsor (Nicholas Carlson), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT03862859 clinical trial studying?

Who can participate in NCT03862859?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT03862859?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT03862859. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT03862859. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.