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Recruiting Phase 4 NCT07515664

NCT07515664 Vitamin K for Perioperative Warfarin Management

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Clinical Trial Summary
NCT ID NCT07515664
Status Recruiting
Phase Phase 4
Sponsor University of Michigan
Condition Anticoagulant Therapy
Study Type INTERVENTIONAL
Enrollment 20 participants
Start Date 2025-07-03
Primary Completion 2026-08

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
Vitamin KWarfarin (standard without loading)Warfarin (standard with loading)

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 4 studies follow an already-approved treatment in real-world conditions to monitor long-term safety and effectiveness.

This trial targets 20 participants in total. It began in 2025-07-03 with a primary completion date of 2026-08.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

This is a feasibility study of uninterrupted warfarin with a one time dose of Vitamin K before a surgical procedure.

Eligibility Criteria

Inclusion Criteria: * Warfarin therapy for ≥3 months * Use of home INR testing equipment * Scheduled for a surgical procedure that requires INR ≤ 1.5 (typically achieved with warfarin interruption) * INR ≤ 4 on day 7-10 prior to procedure Exclusion Criteria: * Surgical procedure does not require INR ≤1.5 (typically achieved with warfarin interruption) * Surgical procedure with a high risk of bleeding or complications (urologic procedures, bronchoscopy, epidural injections, nerve blocks, spinal surgery) * Warfarin therapy for \< 3 months * Lack of English language proficiency * Use of a Heartmate II or HVAD left ventricular assist device * Recent thrombotic event (within 3 months) * CHA2DS2-VASc score \>6 * INR \>4 on day 7-10 prior to procedure * Hypersensitivity to any component of Vitamin K or simple syrup (used in the compounding process)

Contact & Investigator

Central Contact

Geoffrey Barnes, MD

✉ gbarnes@med.umich.edu

📞 734 936-4000

Principal Investigator

Geoffrey Barnes, MD

PRINCIPAL INVESTIGATOR

University of Michigan

Frequently Asked Questions

Who can join the NCT07515664 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Anticoagulant Therapy. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT07515664 trial and what does that mean for participants?

Phase 4 studies are conducted after a treatment has been approved. They monitor long-term safety and real-world effectiveness in a broader patient population.

Is NCT07515664 currently recruiting?

Yes, NCT07515664 is actively recruiting participants. Contact the research team at gbarnes@med.umich.edu for enrollment information.

Where is the NCT07515664 trial being conducted?

This trial is being conducted at Ann Arbor, United States.

Who is sponsoring the NCT07515664 clinical trial?

NCT07515664 is sponsored by University of Michigan. The principal investigator is Geoffrey Barnes, MD at University of Michigan. The trial plans to enroll 20 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: September 2026  ·  Data Methodology