The Australian drug development company Noxopharm, which listed on the Australian Securities Exchange last August, has taken an important step forward in the treatment of secondary brain cancers, a major cause of death for cancer patients.
Noxopharm is working with universities and research institutions in Australia and Hong Kong with the goal of using its front-line drug, NOX66, in clinical trials in 2018 to treat aggressive secondary brain tumours.
Pre-clinical testing has shown that NOX66 acts as the “delivery vehicle” for the active drug compound idronoxil to cross the mammalian blood-barrier (the body’s defence mechanism to protect the brain), where it potentially enhances the ability of current chemotherapy and radiotherapy treatments to cure the brain cancers. [NOX66 works by blocking the ability of cancer cells to repair damage, with the result that even the most resistant cancer cells are killed by chemotherapy or radiotherapy.]
Laboratory tests have shown already that idronoxil improves the cancer cell-killing effect of the chemotherapy drug, temozolomide (TMZ), against breast cancer and melanoma (skin cancer) by up to 1000 times, and it is now the goal to see whether this can be repeated with cancers of the brain.
Noxopharm chief executive Graham Kelly says: “The blood-brain barrier is a key hurdle in delivering more effective treatments for patients with cancers involving the brain.
“We know that TMZ crosses that barrier, as does idronoxil, at least in animals when delivered in the form of NOX66. So here we have two drugs capable of reaching cancerous lesions within the brain and which we now know act in a highly synergistic way.
“There is also the prospect of being able to use TMZ to treat secondary brain cancer at the same time as other more potent chemotherapy is being used to treat metastatic deposits of cancer located elsewhere in the body, with the prospect of NOX66 boosting the effectiveness of chemotherapy across the whole body.”
Secondary cancers of the brain involve cancers that start outside of the brain and then spread to the brain, as distinct from the better known primary brain cancers that originate in and remain in the brain.
They are a prominent cause of death for cancer patients, with the incidence of secondary brain cancer estimated to be at least three times greater than that of primary brain cancer. This year in the US, 26,000 people are expected to be diagnosed with an aggressive primary brain cancer; the exact number of cases of secondary brain cancer is unknown, with US estimates ranging between 75,000 – 250,000.
Any form of cancer can spread to the brain, with breast cancer, lung cancer and melanoma accounting for many cases.
Kelly says: “Most patients with secondary brain cancer have a poor prognosis because surgery and radiation are the only common options for treatment, with the position of the cancer often making them inaccessible to surgery.”
Noxopharm, which has offices in Sydney, Melbourne and Hong Kong, listed at 20 cents. It is currently trading around 39 cents, and has been as high 89 cents.