Comparison of Fractional FLOW Reserve Outcomes With Drug-Coated Balloon-Based Versus Drug-Eluting Stent-Only Percutaneous Coronary Intervention Strategies (FLOW-DCB)

September 25, 2026 updated by: Kang Dong Oh, Korea University Guro Hospital

Comparison of Fractional FLOW Reserve Outcomes With Drug-Coated Balloon-Based Versus Drug-Eluting Stent-Only Percutaneous Coronary Intervention Strategies (FLOW-DCB): A Multicenter, Prospective, Randomized Controlled, Non-inferiority Trial

The goal of this clinical trial is to find out whether a treatment strategy based on a drug-coated balloon (DCB) achieves coronary artery function at 6 months that is not worse than a strategy using only drug-eluting stents (DES) by more than a prespecified amount. The study will enroll adults undergoing percutaneous coronary intervention (PCI) for a new coronary artery narrowing (de novo lesion).

The main questions are:

  1. Is fractional flow reserve (FFR) at 6 months noninferior after DCB-based PCI compared with DES-only PCI? FFR is a pressure-based measure used to assess blood flow through a coronary artery.
  2. Does the DCB-based strategy reduce the number and total length of stents implanted?
  3. What cardiovascular events or medical problems, such as cardiovascular death, myocardial infarction, repeat coronary procedures, or bleeding, occur during follow-up?

Investigators will randomly assign 100 participants to one of two treatment strategies. In the DCB-based group, the lesion will first be prepared with a balloon. A DCB will be used if lesion preparation produces a suitable result; a DES may be implanted if needed to achieve a safe and adequate result. In the DES-only group, the lesion will be treated with a DES.

Participants will:

  1. Receive treatment according to their assigned strategy.
  2. Undergo follow-up coronary angiography and FFR measurement at approximately 6 months. For clinical reasons, this examination may take place up to 9 months after the procedure.
  3. Be followed for cardiovascular events through 12 months after randomization.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

  1. Background and objective Drug-coated balloons (DCBs) deliver an antiproliferative drug to the vessel wall during balloon inflation without leaving a permanent metallic implant. Drug-eluting stents (DESs) provide a permanent metallic scaffold that releases an antiproliferative drug. A DCB-based strategy prioritizes DCB treatment after adequate lesion preparation while allowing DES implantation when the procedural result is unsuitable for DCB treatment. Whether this strategy preserves coronary physiological function at follow-up compared with routine DES implantation remains uncertain. The FLOW-DCB trial will test whether DCB-based percutaneous coronary intervention (PCI) is noninferior to DES-only PCI with respect to fractional flow reserve (FFR) measured distal to the target or culprit lesion at approximately 6 months.

  2. Study design and population FLOW-DCB is an investigator-initiated, multicenter, prospective, randomized, parallel-group noninferiority trial conducted at four hospitals in the Republic of Korea. A total of 100 adults with angina or myocardial infarction requiring PCI for a de novo coronary lesion will be randomized 1:1 after diagnostic coronary angiography and before lesion preparation. The target or culprit lesion must be suitable for either strategy and have a reference vessel diameter of at least 2.25 mm. Randomization is web-based and stratified by center and clinical diagnosis at PCI (acute vs. chronic coronary syndrome).

  3. Treatment strategies In the DCB-based PCI group, lesion preparation may include conventional, non-compliant, cutting, or scoring balloons and, when needed, other calcium-modification techniques. An adequately prepared lesion has expansion with a balloon-to-vessel diameter ratio of at least 0.90, residual diameter stenosis of 30% or less, TIMI grade 3 flow, and no flow-limiting dissection or risk of vessel closure. When these conditions are met, the operator will use a paclitaxel-coated DCB (SeQuent Please NEO), sized approximately 1:1 to the reference vessel and covering the prepared segment. DCB delivery within 30 seconds and inflation for 30-60 seconds are recommended when clinically tolerated. DES implantation is permitted for inadequate flow, residual stenosis greater than 30%, substantial recoil, a major dissection, or another procedural reason requiring immediate stenting. Such stenting is part of the assigned DCB-based strategy, not a treatment crossover.

    In the DES-only PCI group, the target or culprit lesion will be treated with a contemporary newer-generation DES according to clinical practice. Intravascular ultrasound or optical coherence tomography may be used in either group at the operator's discretion. Antiplatelet and other medical treatments will be individualized according to current practice, the actual procedure, and the participant's bleeding and ischemic risks.

  4. Assessments and outcomes Follow-up coronary angiography and FFR measurement are planned at 6 months after randomization, with a ±30-day window; follow-up testing may be performed up to 9 months after the procedure for clinical reasons. A pressure-sensing wire will be placed distal to the treated lesion, and FFR will be recorded during maximal hyperemia. Proximal FFR and the pressure difference across the lesion (trans-lesion ΔFFR) will be recorded when feasible. Pressure drift will be checked at the end of measurement. FFR before or immediately after PCI may be obtained but is not mandatory.

    The primary endpoint is mean FFR distal to the target or culprit lesion at follow-up. Secondary physiological and angiographic outcomes include trans-lesion ΔFFR, quantitative coronary angiographic measures, and the total number and length of implanted stents. Exploratory analyses will assess the effect of follow-up timing and changes in FFR when a baseline measurement is available. Clinical events, including death, myocardial infarction, repeat coronary revascularization, lesion or stent thrombosis, and clinically relevant bleeding, will be assessed through 12 months after randomization. Clinical events and safety data will be reviewed by an independent committee.

  5. Statistical considerations The noninferiority margin for the difference in mean distal FFR (DCB-based PCI minus DES-only PCI) is -0.05. Noninferiority will be concluded if the lower bound of the two-sided 95% confidence interval for this difference exceeds -0.05 (one-sided alpha 0.025). The protocol targets at least 25 evaluable FFR measurements per group and randomizes 50 per group to account for unavailable follow-up measurements. The primary analysis will use available FFR measurements within the protocol-defined follow-up window, according to the randomized treatment group; per-protocol and exploratory as-treated analyses are planned. The trial is designed to assess physiological noninferiority and is not powered to establish differences in clinical events.

Study Type

Interventional

Enrollment (Estimated)

100

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Dong Oh Kang, MD, PhD
  • Phone Number: 82-2-2626-3184
  • Email: gelly9@naver.com

Study Contact Backup

  • Name: Soohyung Park, MD, PhD
  • Phone Number: +82-2-2626-1108
  • Email: shp503@naver.com

Study Locations

  • South Korea
      • Seoul, South Korea, 02841
        • Korea University Anam Hospital
        • Contact:
      • Seoul, South Korea, 08308
        • Korea University Guro Hospital
        • Contact:
        • Contact:
      • Seoul, South Korea, 04763
        • Hanyang University Seoul Hospital
        • Contact:
      • Seoul, South Korea, 01450
        • Hanil General Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

19 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. Adults aged 19 years or older.
  2. Patients requiring coronary revascularization for angina or myocardial infarction.
  3. A target or culprit lesion suitable for both DCB and DES treatment.
  4. Reference vessel diameter of the target or culprit lesion ≥2.25 mm.
  5. Voluntary written informed consent after an explanation of the study objectives and procedures.
  6. For foreign nationals, ability to communicate in Korean.

Exclusion Criteria:

  1. Active bleeding, a clinically significant bleeding tendency, or a coagulation disorder.

  2. Hypersensitivity or a contraindication to aspirin, P2Y12 inhibitors, or components of a DES or DCB (drug, polymer, or metal).

  3. Refractory cardiogenic shock.

  4. Angiographic exclusion:

    • Target lesion in ISR (in-stent restenosis).
    • Target lesion in a bypass graft.
    • Chronic total occlusion
    • Left main coronary artery disease.

  5. History of stent thrombosis.

  6. Expected survival of less than 1 year because of comorbid illness.

  7. Left ventricular ejection fraction ≤20%.

  8. Pregnancy or breastfeeding.

  9. In the investigator's judgment, unsuitable for study participation for clinical or anatomical reasons.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: DCB-based PCI group

In the DCB-based PCI group, lesion preparation may include conventional, non-compliant, cutting, or scoring balloons and, when needed, other calcium-modification techniques. An adequately prepared lesion has expansion with a balloon-to-vessel diameter ratio of at least 0.90, residual diameter stenosis of 30% or less, TIMI grade 3 flow, and no flow-limiting dissection or risk of vessel closure. When these conditions are met, the operator will use a paclitaxel-coated DCB (SeQuent Please NEO), sized approximately 1:1 to the reference vessel and covering the prepared segment. DCB delivery within 30 seconds and inflation for 30-60 seconds are recommended when clinically tolerated. DES implantation is permitted for inadequate flow, residual stenosis greater than 30%, substantial recoil, a major dissection, or another procedural reason requiring immediate stenting. Such stenting is part of the assigned DCB-based strategy, not a treatment crossover.
Device: Drug-coated balloon-based intervention

In the DCB-based PCI group, lesion preparation may include conventional, non-compliant, cutting, or scoring balloons and, when needed, other calcium-modification techniques. An adequately prepared lesion has expansion with a balloon-to-vessel diameter ratio of at least 0.90, residual diameter stenosis of 30% or less, TIMI grade 3 flow, and no flow-limiting dissection or risk of vessel closure. When these conditions are met, the operator will use a paclitaxel-coated DCB (SeQuent Please NEO), sized approximately 1:1 to the reference vessel and covering the prepared segment. DCB delivery within 30 seconds and inflation for 30-60 seconds are recommended when clinically tolerated. DES implantation is permitted for inadequate flow, residual stenosis greater than 30%, substantial recoil, a major dissection, or another procedural reason requiring immediate stenting. Such stenting is part of the assigned DCB-based strategy, not a treatment crossover.

Other Names:
  • Paclitaxel-coated balloon-based intervention
Active Comparator: DES-only PCI group

In the DES-only PCI group, the target or culprit lesion will be treated with a contemporary newer-generation DES according to clinical practice.
Device: Drug-eluting stent-based intervention

In the DES-only PCI group, the target or culprit lesion will be treated with a contemporary newer-generation DES according to clinical practice.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Distal FFR at the target or culprit lesion
Time Frame: 6 months (±30 days; up to 9 months if necessary)

Follow-up coronary angiography will be performed at 6 months (±30 days; up to 9 months if necessary), and distal FFR beyond the target or culprit lesion will be measured with a commercially available pressure wire as the primary outcome.
6 months (±30 days; up to 9 months if necessary)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Trans-lesion ΔFFR
Time Frame: 6 months (±30 days; up to 9 months if necessary)

Difference between FFR measured proximal and distal to the target or culprit lesion.
6 months (±30 days; up to 9 months if necessary)
Intermediate-term pressure gain (exploratory)
Time Frame: 6 months (±30 days; up to 9 months if necessary)

Change in distal FFR from baseline to follow-up in patients with a preprocedural FFR measurement.
6 months (±30 days; up to 9 months if necessary)
Overall stent burden
Time Frame: Immediately after index procedure

Between-group differences in the total number and length of implanted stents
Immediately after index procedure
Quantitative coronary angiography (QCA) measures
Time Frame: 6 months (±30 days; up to 9 months if necessary)

Between-group differences in minimum lumen diameter and percentage diameter stenosis of the target or culprit lesion
6 months (±30 days; up to 9 months if necessary)
Physiological outcomes by follow-up timing (exploratory)
Time Frame: 6-7 months vs. 8-9 months

Distal FFR and trans-lesion ΔFFR at 6-7 versus 8-9 months.
6-7 months vs. 8-9 months
Cardiovascular death
Time Frame: From randomization through 12 months

Number of participants who die from cardiovascular causes, including sudden cardiac death; death due to acute myocardial infarction, heart failure, or cardiogenic shock; other cardiovascular causes; and death of unknown cause without an undisputed noncardiovascular cause.
From randomization through 12 months
All-cause death
Time Frame: From randomization through 12 months

Number of participants who die from any cause during follow-up.
From randomization through 12 months
Target-Vessel Myocardial Infarction
Time Frame: From randomization through 12 months

Number of participants with myocardial infarction attributed to the target vessel treated during the index procedure. Myocardial infarction is adjudicated using the protocol criteria adapted from the Fourth Universal Definition of Myocardial Infarction.
From randomization through 12 months
Nonfatal Myocardial Infarction
Time Frame: From randomization through 12 months

Number of participants with myocardial infarction that does not result in death. Spontaneous and procedure-related myocardial infarctions are included when they meet the protocol criteria adapted from the Fourth Universal Definition of Myocardial Infarction.
From randomization through 12 months
Clinically Indicated Target-Lesion Revascularization
Time Frame: From randomization through 12 months

Number of participants undergoing repeat percutaneous coronary intervention of the target lesion or coronary bypass surgery for target-lesion disease when revascularization is clinically indicated. The protocol requires diameter stenosis of at least 50% by quantitative coronary angiography together with corresponding ischemia on functional testing, ischemic electrocardiographic changes at rest, typical ischemic symptoms, a positive invasive physiological test (FFR ≤0.80 or instantaneous wave-free ratio ≤0.89), or diameter stenosis of at least 70% even without another ischemic criterion.
From randomization through 12 months
Clinically Indicated Target-Vessel Revascularization
Time Frame: From randomization through 12 months

Number of participants undergoing repeat percutaneous coronary intervention or coronary bypass surgery involving any segment of the target vessel when revascularization is clinically indicated. Clinical indication is determined using the protocol criteria for angiographic stenosis and symptoms, electrocardiographic changes, functional testing, or invasive physiological testing.
From randomization through 12 months
Any Revascularization
Time Frame: From randomization through 12 months

Number of participants undergoing any coronary revascularization after the index procedure, including percutaneous coronary intervention or coronary bypass surgery in a target or nontarget vessel, regardless of whether the procedure is classified as clinically indicated.
From randomization through 12 months
Definite or Probable Lesion or Stent Thrombosis
Time Frame: From randomization through 12 months

Number of participants with definite or probable thrombosis involving the treated target lesion or an implanted stent. Stent thrombosis is classified according to Academic Research Consortium criteria. For an unstented drug-coated balloon-treated lesion, definite lesion thrombosis is angiographically confirmed thrombus at the treated site with evidence of acute ischemia, or pathologically confirmed thrombus. Probable lesion thrombosis is myocardial infarction associated with documented acute ischemia in the treated lesion's territory, without angiographic confirmation of thrombus or another obvious cause.
From randomization through 12 months
Cardiovascular Death or Target-Vessel Myocardial Infarction
Time Frame: From randomization through 12 months

Number of participants who experience cardiovascular death or myocardial infarction attributed to the target vessel, whichever occurs first. Components are defined according to the protocol criteria.
From randomization through 12 months
All-Cause Death or Nonfatal Myocardial Infarction
Time Frame: From randomization through 12 months

Number of participants who die from any cause or experience a nonfatal myocardial infarction, whichever occurs first. Myocardial infarction is defined according to the protocol criteria.
From randomization through 12 months
Target-Vessel Failure
Time Frame: From randomization through 12 months

Number of participants who experience cardiovascular death, target-vessel myocardial infarction, or clinically indicated target-vessel revascularization, whichever occurs first.
From randomization through 12 months
Target-Lesion Failure
Time Frame: From randomization through 12 months

Number of participants who experience cardiovascular death, target-vessel myocardial infarction, or clinically indicated target-lesion revascularization, whichever occurs first.
From randomization through 12 months
Clinically Relevant Bleeding
Time Frame: From randomization through 12 months

Number of participants with Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding. These categories include overt bleeding requiring clinical evaluation or treatment (type 2), major bleeding (type 3), and probable or definite fatal bleeding (type 5), as defined in the protocol.
From randomization through 12 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Korea University Guro Hospital

Collaborators

B. Braun Melsungen AG

Investigators

  • Principal Investigator: Dong Oh OK Kang, MD, PhD, Cardiovascular Center, Korea University Guro Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

November 9, 2026

Primary Completion (Estimated)

September 30, 2028

Study Completion (Estimated)

September 30, 2029

Study Registration Dates

First Submitted

September 25, 2026

First Submitted That Met QC Criteria

September 25, 2026

First Posted (Actual)

October 1, 2026

Study Record Updates

Last Update Posted (Actual)

October 1, 2026

Last Update Submitted That Met QC Criteria

September 25, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • FLOW-DCB_KUGH

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

IPD Plan Description

Deidentified individual participant data may be shared with qualified researchers upon reasonable request and after approval of a submitted research proposal by the principal investigator and/or study steering committee. Data sharing will be conducted in accordance with applicable ethical and regulatory requirements.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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