Time is running out for teenage cancer patient, but 'sliver of hope' on horizon

Brigette Metzler is holding onto a "sliver of hope" despite her 16-year-old son Coby's devastating terminal brain cancer diagnosis.

But she fears time will run out before he can access a promising new drug trial offering hope to children with a "dismal prognosis".

"The timeline for delivery of the trial does mean that some children will die waiting for a place," she said.

"My son is likely to be one of them."

The new personalised vaccine for children with deadly brain cancers is called PaedNeoVax (PTX-108) and uses mRNA technology.

Small samples of the patient's tumour are used to create the customised vaccine, which uses the body's immune system (T-cells) to detect and attack cancer markers, or proteins, on the surface of tumour cells.

A world-first trial of the vaccine is set to begin in Australia soon, but a date is yet to be set.

Facing the prospect that her son will not have a long enough life expectancy to qualify for the trial, the self-described "problem-solving mum" is desperately trying to find another way to access the vaccine.

"The clock is really ticking down, and this is not a time for giving up in the face of adversity,"

she said.

With the help of family and friends with expertise in law and medicine, Ms Metzler has worked on a paper attempting to persuade decision-makers.

It addresses the legal and ethical concerns around delivering the untested vaccine to her dying son outside of the trial.

She said while she felt overwhelmed and powerless, she was driven by the "arrogance of love" in the face of what appeared to be an impossible situation.

"I can't not try because I have to be able to live with myself," she said.

Coby Metzler is also appealing to Federal Health Minister Mark Butler and others.

"My life is in your hands. Please help me," he said.

The diagnosis

Coby was diagnosed 14 months ago with level four brain cancer and given a 12 to 18-month life expectancy.

"Coby wanted to train to become a paediatric psychologist, to travel, and eventually to find love and to become a dad one day," his mum said.

At the end of 2024, Coby started to feel unwell. He had irregular blood pressure, then developed a tremor on his right side and later his face on one side drooped.

After several hospital visits and specialist appointments, an MRI in June 2025 revealed he had a Diffuse Midline Glioma (DMG).

"The worst of the worst,"

Ms Metzler said.

DMG is an aggressive tumour that usually affects children.

It is particularly hard to treat as it spreads through the central nervous system and grows in the thalamus, brain stem and spinal cord.

Coby has been treated with radiation and his family is grateful he was able to access a clinical drug trial in November last year, which has potentially extended his life.

For a time, Coby's tumour decreased in size, but by March this year his cancer began to progress again.

"We now understand that his cancer is progressing into his brain stem, which will take away his functions one by one," Ms Metzler said.

Hope for a personalised vaccine

Brain tumours kill more Australian children than any other disease.

Every year 40 Australian children die of brain cancer.

The world-first Australian study of personalised mRNA vaccines for children with aggressive brain tumours is clinically led by Jordan Hansford of medical research institute SAHMRI and Adelaide University, and scientifically led by Brandon Wainwright of the University of Queensland's Frazer Institute and QIMR Berghofer Medical Research Institute.

"This is a new, personalised approach to treating these especially difficult brain cancers that we believe has huge potential," study chair Professor Hansford said.

The trial will be rolled out at paediatric oncology centres across Australia under strict ethical and regulatory frameworks.

The beginning of the trial will help determine the safest and most effective dose, with initial participants very closely monitored before additional participants are added to the study.

A mum's plea 'in the face of certain death'

The federal government has supported the development of the PTX-108 vaccine through a $2.58 million Medical Research Future Fund grant.

Professor Hansford said there would be children with brain cancer for whom this trial would not be suitable.

"Any study we perform has criteria for entry that is outlined in the trial protocol as approved by Human Research Ethics Committee," he said.

He said in rare circumstances he was aware of families and clinicians seeking access to medicine for patients internationally.

However, he said requests for unapproved drugs outside of a trial are handled directly between the medical team, family, and manufacturer, with no trial group involvement.

Additionally, he said that PTX-108 was an experimental vaccine not currently available for purchase anywhere in the world.

Ms Metzler is seeking federal government funding for her son to access the treatment outside the trial when it becomes available.

"So that families … don't need to hope they have enough financial and social resources available to fund treatments that might make a radical difference to their children, extending or even saving their lives."

She is also hoping that decision makers will look at her submission outlining the legal and ethical arguments for allowing access to the vaccine for children outside the trial.

"Australian law expressly permits access to therapies outside of clinical trials," Ms Metzler said.

She said as well as the government providing funding for compassionate access to the vaccine, doctors would need to be supported in delivering it.

"The case for treating with informed consent and guardrails versus doing nothing becomes much more compelling in the face of certain death,"

she said.

"The risk to the patient is always raised as a reason not to, but the simple fact is, the risk to Coby or any other child seeking access outside the trial is no greater than it would be if they were patient number one."

More can be done to help families like Coby's

Brain Tumour Alliance Australia board director Oliver Jarrett said there needed to be more options for people like Coby.

"You can imagine if there is a potential treatment in sight that you might be able to benefit from, it's heartbreaking not to be able to access it," Mr Jarrett said.

The former pharmaceutical executive said it was challenging for the government to pay for access to a medication that is yet to be proven safe.

Instead, he would like to see drug companies provide true compassionate access to treatments whilst they are on trial.

"If it hasn't been studied then provide it free of charge, that gives patients an option, and it doesn't force the government into a price point," he said.

He said Australia currently only secured about 5-10 per cent of the world's phase two and three cancer trials.

"There are at least 10 times more potential treatments that are being studied around the world that people aren't able to access within Australia," he said.

Mr Jarrett said one way of lifting the number of advanced cancer trials in Australia would be having faster approvals of medications under the Pharmaceutical Benefits Scheme (PBS).

He said that would give drug companies an incentive to invest in further trials.

A federal Department of Health spokesperson said a medicine could not be listed on the PBS unless the Pharmaceutical Benefits Advisory Committee (PBAC) made a recommendation in favour of listing.

"The PBAC is an independent and expert body, comprising doctors, health professionals, health economists and consumer representatives," the spokesperson said.

"The PBAC’s consideration is generally initiated when the pharmaceutical company responsible for a medicine applies for PBS listing for specific conditions."

Patient access to trials was a matter for pharmaceutical companies, they said.

 'An agonising balance'

Liz Dawes, the CEO and founder of the Robert Connor Dawes Foundation, has also lost a child to brain cancer.

"I deeply empathise with the Metzler family's search for options. Every parent in this position is acting out of pure love," she said.

 The foundation invested in the early stages of designing and developing the mRNA vaccine for paediatric brain cancer.

 "Unfortunately, the reality we face with untested therapies is that without clinical trials, we simply don't have the safety blueprint needed to protect a sick child from accidental harm," Ms Dawes said.

 She said there needed to be faster access to newer treatments.

"However, we must know those treatments won't make a child's suffering worse. It's an agonising balance, and there are simply no easy answers."