Key points
- Common worming drug shows early promise against brain cancer in lab studies
- Animal research found slower tumour growth and improved survival in mice
- Human trials remain limited, with effectiveness still unproven
A drug widely used to combat intestinal worms has shown promise in treating brain tumours, with scientists calling for more trials to confirm it works in humans.
A systematic review published in the British Journal of Clinical Pharmacology and co-authored by Bond University researchers found mebendazole (MBZ) consistently slowed tumour growth in laboratory and animal tests.
It doubled survival rates in mice, while in one study MBZ combined with radiotherapy left more than half of mice tumour-free over the long term.
Primary malignant brain tumours such as glioblastoma, diffuse midline glioma, medulloblastoma and meningioma rank among the deadliest of human cancers.
Even with surgery, radiotherapy and chemotherapy, just 22 per cent of patients survive five years.
For glioblastoma, the most common and aggressive form, most patients survive only 12 to 16 months after diagnosis.
“Brain cancer is such a big issue because it's very difficult to treat,” said Bond University cancer researcher Dr Liam O'Callaghan, one of the authors of the paper.
The drug under study, MBZ, is an oral deworming medicine that treats threadworm, roundworm and whipworm infections in humans.
Researchers conducted a systematic review of 22 studies examining whether it could fight brain tumours.
Laboratory and animal evidence suggests MBZ attacks tumours through at least six distinct mechanisms, including disrupting the structural scaffolding cancer cells need to divide, blocking the formation of new blood vessels that feed tumours, disrupting the chemical messages that drive tumour growth, and impairing the DNA repair processes that allow tumours to survive radiotherapy.
“I thought it was interesting that it seemed to act on the cancer cells in several different ways rather than just one single pathway,” Dr O'Callaghan said.
MBZ also appears to enhance the effects of both chemotherapy and radiotherapy.
However, human studies present a less encouraging picture.
Early trials in both adults and children show that high doses of oral MBZ are generally safe, but evidence it slows or reduces tumour growth remains modest, inconsistent and inconclusive.
“We've got quite a lot of research in animals and cell lines which look promising, but the human studies, it's still quite limited,” Dr O'Callaghan said.
The authors concluded that MBZ should be regarded as a promising but unproven candidate and should not be used routinely outside research settings.
Dr O'Callaghan said the findings highlighted the need for larger, better-designed clinical trials to determine whether the drug could play a role in treating brain cancer.
Mebendazole is the latest example of a drug being repurposed for possible cancer treatment, alongside metformin and aspirin.
Researchers from Grifith University were also involved in the study.