Phase 3 study for people with Breast Cancer

Recruiting Phase 3

Sources: ClinicalTrials.gov Checked: 11 October 2026 Not medical advice

This trial at a glance

Status Recruiting

Phase Phase 3

Sponsor Ontario Clinical Oncology Group (OCOG)

Registry number NCT05417516

Started 20 November 2023 Today 16 October 2026 Estimated completion 1 November 2029

Where this trial is running

Trial sites and the status recorded for each
Site	City	State or country	Status at this site
GenesisCare Darlinghurst	Darlinghurst	NSW	Recruiting
GenesisCare Hurstville	Hurstville	NSW	Recruiting
GenesisCare Mater Hospital	North Sydney	NSW	Recruiting
GenesisCare Bundaberg	Bundaberg	QLD	Recruiting
GenesisCare Southport	Southport	QLD	Recruiting
GenesisCare Tugun	Tugun	QLD	Recruiting
GenesisCare Hervey Bay	Urraween	QLD	Recruiting
GenesisCare St Andrew's	Adelaide	SA	Recruiting
GenesisCare Bedford Park	Bedford Park	SA	Recruiting
GenesisCare Wembley	Wembley	WA	Recruiting
GenesisCare Fiona Stanley Hospital	Murdoch	WA	Recruiting
GenesisCare Hollywood	Nedlands	WA	Recruiting

voxsanity.com.au · trial sites from public registries · registry record synced 11 October 2026 · not medical advice

Who can join

Age 50 Years to 120 Years

Sex Female participants only

Healthy volunteers Not accepted

Enrolment target 910

The official eligibility criteria

Registry text, reproduced exactly. These are the words the trial's sponsor published on ClinicalTrials.gov. They have not been edited, shortened or rewritten, and they are written for researchers rather than for patients.

Inclusion Criteria:

For inclusion in this study, patients must fulfill all of the following criteria:

1. Female with a new histological diagnosis of invasive carcinoma of the breast with no evidence of metastatic disease (see AJCC TNM Cancer Staging, Appendix II).

2. Treated by BCS with microscopically clear resection margins \>= 1mm for invasive and non-invasive disease or no residual disease on re-excision.

3. Negative axillary node involvement as determined by either sentinel lymph node biopsy or axillary node dissection or clinical assessment with a negative axillary ultrasound and/or biopsy, for women with unifocal tumours \<= 2cm, histologic grade 1 or 2, ER or PR+ and HER2-ve that are being planned for endocrine therapy

Exclusion Criteria:

Patients who satisfy any of the following exclusion criteria are NOT eligible for this study:

1. Age less than 50 years.

2. Known to be BRCA 1 and/or BRCA 2 positive.

3. Tumour size \>3cm in greatest diameter on pathological examination.

4. Evidence of extensive intraductal component (EIC) (defined as an invasive tumour with a ductal carcinoma in situ (DCIS) component comprising at least 25% and extending beyond the invasive component to surrounding normal breast tissue) with the following exception: smaller tumours with EIC where the combined size (of the invasive and DCIS components) are \<= 3cm remain eligible

5. Evidence of a DCIS component \> 3cm

6. Lobular carcinoma only.

7. More than one primary tumour in different quadrants of the same breast (patients with multifocal breast cancer are eligible).

8. Synchronous or previous contralateral breast cancer (patients with contralateral DCIS or LCIS are eligible).

9. History of non-breast malignancy within the last 5 years other than treated non-melanoma skin cancer or treated in-situ carcinoma.

10. Known pregnancy or currently lactating.

11. Inability to localize tumour bed on CT planning (no evidence of surgical clips or seroma).

12. Inability to plan the patient for the experimental technique.

Dates on the record

Started 20 November 2023

Estimated completion 1 November 2029

Registry last updated 14 September 2026

Checked by Voxsanity 11 October 2026

Results, publications and the official record

No results are posted on the official record yet.
No publications are listed on the official record yet.
Official record and contacts on ClinicalTrials.gov – contact details for each site are kept there, and are not copied onto this page.

Sources and dates

ClinicalTrials.gov – the record this page reformats
ClinicalTrials.gov processing date: 14 September 2026.
This page last checked by Voxsanity: 11 October 2026.

Voxsanity reformats data from public registries into this layout. It does not edit, interpret or add to what the registry published.

Not medical advice.

Individual trial records are refreshed on a rolling basis rather than all at once, so a record may be up to several weeks old. Each trial page and trial card shows the date its own record was last synced. Where a record has lagged, its status, sites and enrolment can differ from the current registry state in either direction, so check the registry link on the trial page before acting on them.

Letter for your doctor

A one-page summary of this trial to print or email to your GP. It carries the registry's own record of the trial and its eligibility criteria, and nothing Voxsanity has written about whether it suits you.

Voxsanity

Clinical trials recruiting in Australia, from the public registries · voxsanity.com.au

Date:

To: My Doctor

Re: Clinical trial enquiry

I am writing to enquire about the following clinical trial, which may be relevant to my care:

Trial: NCT05417516

Sponsor: Ontario Clinical Oncology Group (OCOG)

Phase: Phase 3

Status: Recruiting

Condition: Breast Cancer

More information: https://clinicaltrials.gov/study/NCT05417516

Eligibility criteria, as the registry published them

Reproduced exactly, unedited. Written for researchers rather than for patients.

Inclusion Criteria:

For inclusion in this study, patients must fulfill all of the following criteria:

Female with a new histological diagnosis of invasive carcinoma of the breast with no evidence of metastatic disease (see AJCC TNM Cancer Staging, Appendix II).
Treated by BCS with microscopically clear resection margins >= 1mm for invasive and non-invasive disease or no residual disease on re-excision.
Negative axillary node involvement as determined by either sentinel lymph node biopsy or axillary node dissection or clinical assessment with a negative axillary ultrasound and/or biopsy, for women with unifocal tumours <= 2cm, histologic grade 1 or 2, ER or PR+ and HER2-ve that are being planned for endocrine therapy

Exclusion Criteria:

Patients who satisfy any of the following exclusion criteria are NOT eligible for this study:

Age less than 50 years.
Known to be BRCA 1 and/or BRCA 2 positive.
Tumour size >3cm in greatest diameter on pathological examination.
Evidence of extensive intraductal component (EIC) (defined as an invasive tumour with a ductal carcinoma in situ (DCIS) component comprising at least 25% and extending beyond the invasive component to surrounding normal breast tissue) with the following exception: smaller tumours with EIC where the combined size (of the invasive and DCIS components) are <= 3cm remain eligible
Evidence of a DCIS component > 3cm
Lobular carcinoma only.
More than one primary tumour in different quadrants of the same breast (patients with multifocal breast cancer are eligible).
Synchronous or previous contralateral breast cancer (patients with contralateral DCIS or LCIS are eligible).
History of non-breast malignancy within the last 5 years other than treated non-melanoma skin cancer or treated in-situ carcinoma.
Known pregnancy or currently lactating.
Inability to localize tumour bed on CT planning (no evidence of surgical clips or seroma).
Inability to plan the patient for the experimental technique.

A treatment being studied in a clinical trial is generally not yet listed on the PBS. Where a medicine is not approved or not available through a trial, the TGA Special Access Scheme may allow a registered health practitioner to access unapproved therapeutic goods for individual patients.

Not medical advice. Voxsanity reformats information published by public registries. It does not give medical advice and is not a substitute for talking to your doctor.