HOST-BR Trial: Three-Month DAPT Shows Sweet Spot for Both High and Low Bleeding Risk Patients

 In a Late-Breaking Clinical Trial at ACC.25, the HOST-BR study delivered new clarity on the optimal duration of dual antiplatelet therapy (DAPT) following stent implantation. The key finding? Three months of DAPT appears to be the Goldilocks zone—long enough to prevent events but short enough to reduce bleeding, across both high and low bleeding risk patients.

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Study Overview

• Type: Multicenter, randomized, investigator-initiated trial

• Population: 4,897 patients from South Korea

  • 1,598 patients with high bleeding risk (HBR)

  • 3,299 patients with low bleeding risk (LBR)

• DAPT Regimens Compared:

  • HBR: 1 month vs. 3 months

  • LBR: 3 months vs. 12 months

Note: Use of P2Y12 inhibitors during or after DAPT was clinician’s choice.

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Inclusion Criteria

• Adults undergoing coronary stenting

• Ability to tolerate DAPT for at least 1 month post-procedure

• Classified as either high or low bleeding risk based on validated criteria

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Exclusion Criteria

• Planned surgery requiring interruption of antiplatelet therapy

• Contraindication to aspirin or P2Y12 inhibitors

• Active bleeding or bleeding diathesis

• Life expectancy <1 year

• History of nonadherence

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Primary Endpoints

1. Net Adverse Clinical Events (NACE):

   • Composite of all-cause death, myocardial infarction (MI), stent thrombosis, stroke, or major bleeding

2. Major Adverse Cardiac or Cerebral Events (MACCE):

   • Composite of cardiovascular death, MI, stent thrombosis, or ischemic stroke

3. Actionable Bleeding:

   • Clinically significant bleeding requiring medical intervention

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Key Findings

High Bleeding Risk (HBR) Patients:

• Three-month DAPT had fewer events than one-month:

  • NACE: 14.4% (3 mo) vs. 18.4% (1 mo)

  • MACCE: 6.4% (3 mo) vs. 10.3% (1 mo)

• Bleeding rates were similar:

  • 17.9% (3 mo) vs. 15.6% (1 mo)

Low Bleeding Risk (LBR) Patients:

• Similar efficacy between three-month and twelve-month DAPT:

  • NACE: 4% (3 mo) vs. 5.7% (12 mo)

  • MACCE: 2.5% (3 mo) vs. 2.8% (12 mo)

• Significantly less bleeding in three-month group:

  • 9.2% vs. 13.7%

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Study Limitations

• Conducted exclusively in South Korea

• Clopidogrel was used in ~80% of patients as the second antiplatelet agent, reflecting East Asian practice

• Results may vary in populations using more potent agents like ticagrelor

Still, the findings provide valuable insight into tailoring DAPT duration globally.

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Take-Home Points

• Three months of DAPT is superior to one month in HBR patients—reduces cardiac events without increasing bleeding.

• In LBR patients, three months is safer than 12 months—less bleeding with similar efficacy.

• These results may support redefining standard DAPT duration for both high and low bleeding risk populations.

• A pragmatic approach using shorter DAPT could improve patient safety, especially in older adults and those with multiple comorbidities.

• Further studies needed for non-Asian populations and those using different P2Y12 inhibitors.

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The HOST-BR trial reminds us that less can sometimes be more, and in the case of DAPT, three months might be just right.