Trial Review

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Trial registered on ANZCTR


Registration number
Help: Registration number
ACTRN12626001206314
Ethics application status
Help: Ethics application status
Approved
Date submitted
Help: Date submitted
1/09/2026
Date registered
Help: Date registered
30/09/2026
Date last updated
Help: Date last updated
30/09/2026
Date data sharing statement initially provided
Help: Data sharing statement date
30/09/2026
Type of registration
Help: Type of registration
Retrospectively registered

Titles & IDs
Public title
D.A.R.E.S: Direct-acting oral anticoagulant (DOAC) Allows Routine Endoscopic Snaring
Scientific title
D.A.R.E.S: DOAC Allows Routine Endoscopic Snaring. Assessing the impact of minimal DOAC withholding prior to colonoscopy on post-operative bleeding rates
Additional trial identifiers [1] 315001 0
None
Universal Trial Number (UTN)
Trial acronym
DARES
Related trial records

Health condition
Health condition(s) studied:
Delayed post-cold snare polypectomy bleeding 338350 0
colonoscopy 343539 0
Condition category
Condition code
Oral and Gastrointestinal 334647 334647 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of the intervention or exposure
The primary cohort to be observed comprises adult patients taking direct oral anticoagulants (DOACs) who, as part of standard clinical care at their participating centre, withhold their DOAC therapy only on the morning of their colonoscopy and undergo cold snare polypectomy.

Withholding DOAC therapy only on the morning of colonoscopy is not an intervention imposed on participants as a consequence of participation in this study. DARES is a prospective observational cohort study. Participants will receive the current standard of care at their participating centre, and their peri-procedural anticoagulation management will not be altered for the purposes of the study.

The protocol notes that withholding DOAC therapy only on the morning of colonoscopy with cold snare polypectomy is established practice in a number of centres in Australia and internationally, supported by Japanese guidelines and published observational data. Other international guidelines recommend longer periods of DOAC interruption, and clinical practice therefore varies between centres.

Patients will follow the usual peri-procedural anticoagulation instructions of their treating centre/clinician regardless of whether they participate in the study. Patients whose DOAC has been withheld for longer than 24 hours may also be included as an observational comparator subgroup, with a planned subgroup analysis comparing outcomes with the primary morning-only withholding cohort.

The DOACs included in the study are apixaban, rivaroxaban and dabigatran.

The study does not prescribe a study-specific time for recommencement of DOAC therapy. Recommencement will occur according to the treating clinician's usual practice and the participating site's standard peri-procedural anticoagulation management. Participation in the study will therefore not alter the timing of recommencement of anticoagulation.

DOAC management, including medication name, dose and relevant peri-procedural anticoagulation information, will be prospectively recorded as part of the study data collection. The study does not require blood testing or measurement of DOAC levels before colonoscopy. Compliance with the instructed withholding period will be established from the patient's medication history/verbal confirmation and clinical record as part of the routine pre-procedure assessment.

There are no study-specific questionnaires, quality-of-life instruments or additional physical assessments required of participants. Patients undergo the usual pre-procedure clinical assessment and receive the usual bowel preparation, sedation and colonoscopy care.

Participants will receive the routine post-colonoscopy follow-up telephone call from endoscopy staff approximately 14 days after colonoscopy. This call is used to identify post-procedure complications and outcomes. The patient's medical record will also be reviewed at day 14 to collect relevant study outcome data. No additional participant questionnaires or physical examinations are required solely for research purposes.
Intervention code [1] 331608 0
Not applicable
Description of the comparator or control
The observational comparator subgroup comprises patients whose DOAC has been withheld for greater than 24 hours as part of their usual clinical care. Outcomes in this subgroup will be compared with those of the primary cohort of patients who withhold their DOAC only on the morning of their procedure.

The study does not allocate participants to either DOAC withholding strategy. The duration of DOAC withholding is determined by the treating clinician and/or participating centre according to usual clinical practice. The comparison between these groups is therefore observational and does not represent a study-assigned intervention.

The protocol anticipates that the greater-than-24-hour withholding subgroup will be relatively small, which may limit statistical analysis.
Control group
Active

Outcomes
Primary outcome [1] 342324 0
Rate of delayed post-polypectomy bleeding observed within 14 days of cold snare polypectomy
Timepoint [1] 342324 0
day 14 post-polypectomy
Secondary outcome [1] 450324 0
1) the rates of immediate bleeding post-polypectomy (lasting at least 2 minutes) requiring prophylactic endoscopic intervention
Timepoint [1] 450324 0
day 14 post-colonoscopy
Secondary outcome [2] 467685 0
2) the rates of hospitalisation with delayed post-polypectomy bleeding,
Timepoint [2] 467685 0
day 14 post-colonoscopy
Secondary outcome [3] 467686 0
3) the rates of blood transfusions for patients with delayed post-polypectomy bleeding,
Timepoint [3] 467686 0
day 14 post-colonoscopy
Secondary outcome [4] 467687 0
4) the proportion of delayed post-polypectomy patients requiring repeat colonoscopy with endoscopic intervention or surgery,
Timepoint [4] 467687 0
day 14 post-colonoscopy
Secondary outcome [5] 467688 0
5) the rate of thromboembolic events from 48 hours pre-procedure to 14 days following cold snare polypectomy,
Timepoint [5] 467688 0
day 14 post-colonoscopy
Secondary outcome [6] 467689 0
6) the rate of modification to procedure timing due to anticoagulation status.
Timepoint [6] 467689 0
day 14 post-colonoscopy

Eligibility
Key inclusion criteria
1. Aged >=18 years
2. Patient taking DOAC therapy (apixaban, rivaroxaban, dabigatran)
3. Undergo colonoscopy
4. capacity to consent
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Healthy volunteers
No
Key exclusion criteria
1. Aged <18 years
2. Not taking DOAC therapy
3. Hot snare polypectomy

Study design
Purpose
Duration
Longitudinal
Selection
Defined population
Timing
Prospective
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
16/05/2025
Date of last participant enrolment
Anticipated
16/06/2027
Actual
Date of last data collection
Anticipated
30/06/2027
Actual
Sample size
Target
1000
Accrual to date
50
Final
Recruitment in Australia
Recruitment state(s)
QLD,SA,WA,VIC

Funding & Sponsors
Funding source category [1] 319567 0
Charities/Societies/Foundations
Name [1] 319567 0
Australia and New Zealand Endoscopy Leaders Forum
Country [1] 319567 0
Australia
Primary sponsor type
Individual
Name
A/Professor Spiro Raftopoulos - Sir Charles Gairdner Hospital
Address
Country
Australia
Secondary sponsor category [1] 322057 0
None
Name [1] 322057 0
Address [1] 322057 0
Country [1] 322057 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 318130 0
Sir Charles Gairdner and Osborne Park Health Care Group Human Research Ethics Committee
Ethics committee address [1] 318130 0
Ethics committee country [1] 318130 0
Australia
Date submitted for ethics approval [1] 318130 0
28/11/2024
Approval date [1] 318130 0
16/05/2025
Ethics approval number [1] 318130 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 143206 0
A/Prof Spiro Raftopoulos
Address 143206 0
Sir Charles Gairdner Hospital - Hospital Avenue, Nedlands WA 6009 Australia
Country 143206 0
Australia
Phone 143206 0
+61 8 64573333
Fax 143206 0
Email 143206 0
[email protected]
Contact person for public queries
Name 143207 0
Spiro Raftopoulos
Address 143207 0
Sir Charles Gairdner Hospital - Hospital Avenue, Nedlands WA 6009 Australia
Country 143207 0
Australia
Phone 143207 0
+61 8 64573333
Fax 143207 0
Email 143207 0
[email protected]
Contact person for scientific queries
Name 143208 0
Spiro Raftopoulos
Address 143208 0
Sir Charles Gairdner Hospital - Hospital Avenue, Nedlands WA 6009 Australia
Country 143208 0
Australia
Phone 143208 0
+61 8 64573333
Fax 143208 0
Email 143208 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
Yes
Will there be any conditions when requesting access to individual participant data?
Persons/groups eligible to request access:
• Researchers
Conditions for requesting access:
• Yes, conditions apply:
• Requires review on a case-by-case basis by the trial custodian, sponsor or data sharing committee
• Requires a scientifically sound proposal or protocol
• Requires approval by an ethics committee
• Requires a data sharing agreement between data requester and trial custodian or sponsor
What individual participant data might be shared?
• De-identified individual participant data:
• All outcomes data
• Published results
• Primary outcome(s)
• Safety data
What types of analyses could be done with individual participant data?
• Any type of analysis (i.e. no restrictions on data re-use)
• Systematic reviews and meta-analyses
• Studies exploring new research questions
• Health economic analyses
• Studies testing whether findings can be repeated or confirmed
When can requests for individual participant data be made (start and end dates)?
From:
After publication of main results
To:
A finite period of: 7 years
Where can requests to access individual participant data be made, or data be obtained directly?
• Email of trial custodian, sponsor or committee: [email protected]

Are there extra considerations when requesting access to individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.