Pre-clinical data suggests Noxopharm’s anti-cancer drug can boost radiation effect on paediatric brain cancer

Pre-clinical data has confirmed Noxopharm’s (ASX: NOX) experimental idronoxil anti-cancer drug can boost the killing effect of radiation when treating paediatric brain cancer cells.

Noxopharm teamed up the Children’s Cancer Institute to investigate impact of idronoxil (NOX66) on sensitising diffuse intrinsic pontine glioma cancer cells to radiation in a laboratory setting.

Diffuse intrinsic pontine glioma is a “highly aggressive” and “poorly responsive” primary brain cancer in children.

Results from the research revealed idronoxil was able to kill the cancer cells on its own. The drug also sensitised the cells to radiation generating a “significantly” higher destruction level of the cancer cells while using a constant radiation dose.

Noxopharm believes its idronoxil can potentially render cancer cells more susceptible to radiation while ensuring healthy cells are not made more sensitive as well.

“Today’s data fits in with other data showing idronoxil increasing the killing effect of radiation on lung and prostate cancer cells by two-or-three fold,” Noxopharm chief scientific officer Dr John Wilkinson said.

“The radio-enhancing effect of idronoxil, therefore, is looking to be independent of cancer type.”

“On that score, it is worth noting that diffuse intrinsic pontine glioma arises in the brain’s glioma cells, or cells that provide the support structure of the brain.”

Dr Wilkinson added the next stage for testing idronoxil on diffuse intrinsic pontine glioma would be animal research.

“Tumours will be grown in the brains of mice (orthotopic xenografted tumours) and treated with a combination of NOX66 and radiotherapy.”

If these trials are successful, Dr Wilkinson said it would open the door for clinical studies in children.

The research on diffuse intrinsic pontine glioma was part of Noxopharm’s broader study into the impact of idronoxil combined with radiation in treating primary and secondary brain cancers in adults and children.

As part of the research, Noxopharm will also be evaluating the ability of idronoxil to cross the blood-brain barrier in animals, the drug’s capability of killing chemotherapy-resistant glioblastoma multiforme cancer cells, as well as boosting the cancer cells’ sensitivity to radiation.

Diffuse intrinsic pontine glioma

Diffuse intrinsic pontine glioma is the most aggressive form of childhood cancer and is the leading cause of brain-tumour related death in children.

According to Dr Wilkinson, current treatments for diffuse intrinsic pontine glioma are constrained to radiotherapy, which is then further limited due to cancer cells’ location on the brainstem, which controls the body’s vital functions including breathing and heart rate.

He noted this accounts for the cancer’s poor survival rate. Although, radiation can be effective in 90% of the cases, the response is “short-lived” with recurrence generally within 12 months.

“Our aim with NOX66 is to provide a means of achieving greater killing of diffuse intrinsic pontine glioma cells, equivalent to giving a higher dosage of radiotherapy, but without inducing any more harm on healthy brain tissue – and, obviously, we hope to see that translate into longer survival,” Dr Wilkinson said.

Shares in Noxopharm had dipped 1.56% to A$0.63 by late morning trade.