Valve Replacement SurgeryPhase 4CONCLAVENCT07431762
Comparison of Anti-Thrombotic Treatments Between Aspirin and Warfarin During Initial Six Months After Bioprosthetic Heart Valve Replacement
A Phase 4 study testing Aspirin and Vitamin K antagonist(warfarin) in people with Valve Replacement Surgery, run by Asan Medical Center at 3 sites in 2 countries.
Trial summary
This trial is a multinational, multicenter, randomized, open-label, active-controlled clinical trial comparing the safety of aspirin versus vitamin K antagonists (warfarin) as oral antithrombotic therapy during the initial 6 months following tissue valve replacement (aortic or mitral). Read more about this study
- Who is it for?
- Ages 19 years and older
- Conditions the study is for
- Valve Replacement Surgery
- What is being tested?
- Aspirin and Vitamin K antagonist(warfarin)
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 1,058 participants
- Where
- 3 sitesin 2 countries
- Study dates
- 5 Jun 2026to 31 Mar 2031
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 19 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Aged ≥ 19 years with successful surgical bioprosthetic valve replacement
- Bioprosthetic heart valve in aortic or mitral valve positions, for a day postoperatively
- The patient or guardian agrees to the study protocol and the schedule of clinical follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site.
Who cannot join
- Mechanical valve in any heart valve position
- Previous hemorrhagic stroke within the last 3 months
- Clinically overt stroke within the last 3 months
- Current need for anticoagulation (i.e. atrial fibrillation, deep vein thrombosis)
- Unstable postoperative conditions at index point (i.e. requirement mechanical hemodynamic support, disabling complications, stroke [ischemic, embolic], hemorrhagic stroke)
- Hypersensitivity to the main component or constituents of aspirin or vitamin K antagonist
- Pregnant or lactating women
Trial locations and contacts
3 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
3 sites in 2 countries
Japan2 sites, 2 recruiting
- Not yet recruiting
National Cerebral and Cardiovascular Center Hospital
Osaka, 564-8565
Fukushima Satsuki, MD
- Not yet recruiting
Osaka University Hospital
Osaka, 565-0871
Yajima Shin, MD
South Korea1 site, 1 recruiting
- Recruiting
Asan Medical Center
Seoul, 05505
Joon-Bum KIM, MD
About this study
This trial is a multinational, multicenter, randomized, open-label, active-controlled clinical trial comparing the safety of aspirin versus vitamin K antagonists (warfarin) as oral antithrombotic therapy during the initial 6 months following tissue valve replacement (aortic or mitral).
- Conditions
- Valve Replacement Surgery
- Being tested
- Aspirin, Vitamin K antagonist(warfarin)
- Keywords
- aspirin versus vitamin K antagonists
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
AspirinDrug
100mg 1 tablet once daily for 6 months
Vitamin K antagonist(warfarin)Drug
Maintain an INR(International Normalized Ratio) of 2.0 to 3.0 for 6 months
| Study group | Role | What they receive |
|---|---|---|
| Aspirin | Experimental | Antiplatelet Agent Receives: Drug: Aspirin |
| warfarin | Active comparator | Vitamin K antagonist Receives: Drug: Vitamin K antagonist(warfarin) |
What is being measured
The primary outcome is the main question the study is designed to answer.
A composite endpoint is defined as a single outcome that combines multiple clinical events; the occurrence of any one of the component events is considered as meeting the endpoint.
Measured: From registration to 6 months
Secondary outcomes (7)
Rate of all-cause mortality within 6 months
Measured: From registration to 6 months
Number of participants who experienced stroke within 6 months
Measured: From registration to 6 months
Number of participants who experienced transient ischemic attack within 6 months
Measured: From registration to 6 months
Number of participants who experienced systemic embolism within 6 months
Measured: From registration to 6 months
Number of participants who experienced myocardial infarction within 6 months
Measured: From registration to 6 months
Number of participants who experienced major bleeding within 6 months
Measured: From registration to 6 months
Number of participants with valve thrombosis at 6 months
Measured: From registration to 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Feb 2026
- Study start5 Jun 2026
- Primary completion31 Oct 2030 (estimated)
- Study completion31 Mar 2031 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Valve Replacement SurgeryStudies of the same condition, open and under way.
- More trials run by Asan Medical CenterThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 1,058 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Asan Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Joon Bum Kim, Asan Medical Center
- Investigators
- Joon-Bum KIM, MD, Study director, jbkim1975@amc.seoul.kr
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07431762
- Sponsor's protocol ID
- 2025-1499
- Acronym
- CONCLAVE
- Status last verified
- Jul 2026
- First submitted
- 11 Dec 2025
- Last updated
- 6 Jul 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 6 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of Anti-Thrombotic Treatments Between Aspirin and Warfarin During Initial Six Months After Bioprosthetic Heart Valve Replacement
- ClinicalTrials.gov ID
- NCT07431762
- Acronym / sponsor ID
- CONCLAVE / 2025-1499
- Conditions
- Valve Replacement Surgery
- Keywords
- aspirin versus vitamin K antagonists
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 1,058 participants (estimated)
- Lead sponsor
- Asan Medical CenterUniversity, hospital or other
- Study start
- 5 Jun 2026 (actual)
- Primary completion
- 31 Oct 2030 (estimated)
- Study completion
- 31 Mar 2031 (estimated)
- First posted
- 25 Feb 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This trial is a multinational, multicenter, randomized, open-label, active-controlled clinical trial comparing the safety of aspirin versus vitamin K antagonists (warfarin) as oral antithrombotic therapy during the initial 6 months following tissue valve replacement (aortic or mitral).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Aspirin | Experimental | Drug: AspirinAntiplatelet Agent |
| warfarin | Active comparator | Drug: Vitamin K antagonist(warfarin)Vitamin K antagonist |
Who may qualify
- Ages
- 19 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Aged ≥ 19 years with successful surgical bioprosthetic valve replacement
- Bioprosthetic heart valve in aortic or mitral valve positions, for a day postoperatively
- The patient or guardian agrees to the study protocol and the schedule of clinical follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site.
Key exclusion criteria (7 listed)
- Mechanical valve in any heart valve position
- Previous hemorrhagic stroke within the last 3 months
- Clinically overt stroke within the last 3 months
- Current need for anticoagulation (i.e. atrial fibrillation, deep vein thrombosis)
- Unstable postoperative conditions at index point (i.e. requirement mechanical hemodynamic support, disabling complications, stroke [ischemic, embolic], hemorrhagic stroke)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Aspirin100mg 1 tablet once daily for 6 months | Drug | Aspirin |
| Vitamin K antagonist(warfarin)Maintain an INR(International Normalized Ratio) of 2.0 to 3.0 for 6 months | Drug | warfarin |
Primary outcome
A composite endpoint is defined as a single outcome that combines multiple clinical events; the occurrence of any one of the component events is considered as meeting the endpoint.
Time frame: From registration to 6 months
7 secondary outcomes
Rate of all-cause mortality within 6 months
Time frame: From registration to 6 months
Number of participants who experienced stroke within 6 months
Time frame: From registration to 6 months
Number of participants who experienced transient ischemic attack within 6 months
Time frame: From registration to 6 months
Number of participants who experienced systemic embolism within 6 months
Time frame: From registration to 6 months
Number of participants who experienced myocardial infarction within 6 months
Time frame: From registration to 6 months
Number of participants who experienced major bleeding within 6 months
Time frame: From registration to 6 months
Number of participants with valve thrombosis at 6 months
Time frame: From registration to 6 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Jul 2026.
- Individual participant dataSharing planned: Undecided
Related trials for Valve Replacement Surgery
Active, not recruiting
Medtronic Evolut Transcatheter Aortic Valve Replacement in Low Risk Patients
Aortic Valve Stenosis
Recruiting
ARTIST: Aortic Regurgitation Trial Investigating Surgery Versus Trilogy™
Aortic Regurgitation, Aortic Valve Insufficiency
RecruitingObservational study
TRIFORMIS RESILIA Real-world Study Assessing Safety and Performance (TRIBLAZE Study)
Heart Valve Diseases, Heart Diseases
Active, not recruiting
Autus Valve Continued Access Study (CAS)
Congenital Heart Disease
Active, not recruiting
Autus Valve Pivotal Study
Congenital Heart Disease
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Joon-Bum KIM, MD study director
jbkim1975@amc.seoul.kr
3 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Aspirin and Vitamin K antagonist(warfarin) in people with Valve Replacement Surgery, run by Asan Medical Center at 3 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 6 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in Japan, South Korea. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Joon-bum Kim, MD (82230105416, jbkim1975@amc.seoul.kr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
A composite endpoint is defined as a single outcome that combines multiple clinical events; the occurrence of any one of the component events is considered as meeting the endpoint. (time frame: From registration to 6 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Jul 2026.