If this is close to home
This page includes language about advanced illness, prognosis, or palliative care, because that is how the trial's eligibility criteria are written. Seeing it set out plainly can land hard, whether it is about you or about someone you are caring for. You do not have to be at a crisis point to talk to someone.
- Griefline — grief and loss counselling, 9am to 6pm weekdays and midday to 6pm weekends (AEST/AEDT): 1300 845 745
- Carer Gateway — practical and emotional support if you are caring for someone, 8am to 5pm weekdays: 1800 422 737
- Canteen — for 12 to 25 year olds affected by cancer, their own or a family member's: 1800 945 215
- Palliative Care Australia — directory of palliative care services near you: palliativecare.org.au
- Lifeline — 24/7, for any kind of distress, at any hour the services above are closed: 13 11 14
Palliative care is not the same as giving up on treatment, and it is not only for the last weeks of life. It is symptom and comfort care that can run alongside active treatment, including a clinical trial.
Outside Australia? The numbers above are Australian and will not work from overseas. Find a Helpline is a free directory of support and crisis lines in over 130 countries, run by ThroughLine with the International Association for Suicide Prevention.
Voxsanity is not a counselling or medical service, and nothing on this page is medical advice. More Australian services are listed on our support lines page.
Phase 3 study for people with Brain Cancer
Recruiting Phase 3
This trial at a glance
Where this trial is running
| Site | City | State or country | Status at this site |
|---|---|---|---|
| John Hunter Children's Hospital | New Lambton Heights | NSW | Recruiting |
| Children's Hospital in Westmead | Westmead | NSW | Withdrawn |
| Women and Childen's Hospital | Adelaide | SA | Recruiting |
| Monash Children's Hospital | Clayton | VIC | Recruiting |
| Royal Children's Hospital | Parkville | VIC | Recruiting |
| Perth Children's Hospital | Nedlands | WA | Recruiting |
voxsanity.com.au · trial sites from public registries · registry record synced 11 October 2026 · not medical advice
Who can join
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:
In order to be eligible to participate in this study, an individual must meet all of the following criteria:
1. No less than 3 weeks after completion of:
* Primary therapy for:
1. medulloblastoma
OR
2. ependymoma
OR
3. craniopharyngioma
OR
4. germ cell tumours
OR
* Primary therapy for any other brain tumour treated with cranial radiation - at the discretion of the Study PI
OR
* Cranial radiation for relapsed ependymoma
2. Age 7 years to 21 years and 11 months at the time of enrollment
3. Either declare English (or French in accepting sites) as their native language or have had at least two years of schooling in English (or French in accepting sites) at the time of consent
4. Able to swallow tablets either whole, crushed or via a feeding tube and be willing to adhere to the study intervention regimen
5. Meet criteria for normal organ function requirements as described below:
1. Normal renal function defined as: Estimated glomerular filtration rate (eGFR) \> 75ml/min/1.73m²
* eGFR is calculated using the Schwartz formula: eGFR (mL/min/1.73m²) = (0.41 × height in cm) / creatinine in mg/dL
2. Normal liver function defined as:
* Serum glutamic-oxaloacetic transaminase (SGOT) (AST) ≤2.5 x institutional upper limit of normal (ULN) for age and gender
* Serum glutamic pyruvic transaminase (SGPT) (ALT) ≤2.5 x institutional ULN for age and gender
* Total bilirubin \<1.5x institutional ULN for age and gender (patients with documented Gilbert's Disease may be enrolled with Sponsor approval and total bilirubin ≤2.0 x institutional ULN)
6. Informed consent (and assent, where applicable) will be obtained from the participants and/or their legal guardian(s) by study team members delegated to consent for this study
Exclusion Criteria:
Participants who meet any of the following criteria will not be eligible to take part in the trial:
1. Standard score of less than 60 for full scale IQ on the Wechsler Abbreviated Scale of Intelligence, Second Edition (WASI-II) (or other Wechsler Scale of Intelligence for English speaking participants) or pro-rated IQ score on the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) or Wechsler Adult Intelligence Scale (WAIS-IV) for French speaking participants at Screening visit
2. Have a known hypersensitivity to metformin hydrochloride
3. Have unstable and/or insulin-dependent (Type 1) diabetes
4. Have a history of hypoglycemia after 2 years of age
5. Have been diagnosed with acute or chronic metabolic acidosis and/or lactic acidosis or if bicarbonate (Total CO2) is less than 22 mmol/L at the Screening visit
6. Have a history of renal disease or renal dysfunction pre-existing to the diagnosis of Medulloblastoma
7. Have a history of congestive heart failure requiring pharmacologic treatment (including the use of diuretics) within two years prior to study entry
8. Currently taking part in a cognitive rehabilitation intervention study
9. Treatment or planned treatment involving diuretics
10. Current or planned treatment with cationic drugs excreted by the kidneys (e.g. amiloride, cimetidine, digoxin, morphine, nifedipine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, and vancomycin)
11. Current or planned treatment with concomitant medications with potential unacceptable interaction with metformin including, lamotrigine, beta blockers, angiotensin-converting enzyme (ACE) inhibitors, glycopyrrolate, and carbonic anhydrase inhibitors, or at the discretion of the Site PI or delegate for medications with potential interactions such as sertraline, lansoprazole and omeprazole.
12. Pernicious anemia (according to results of the Screening visit blood draw)
13. Current use of metformin hydrochloride
14. Any condition or diagnosis, that could in the opinion of the Site PI or delegate interfere with the participant's ability to comply with study instructions, might confound the interpretation of the study results, or put the participant at risk
15. Are receiving palliative care
Dates on the record
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: 24 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.