Anti-cancer Drug Treatment Trial for DFTD Completed
A recent pilot study, which investigated the effectiveness of a novel plant molecule with anti-cancer properties has shown some encouraging results for the localised treatment of tumours caused by Devil Facial Tumour Disease (DFTD). The preliminary findings indicate that the molecule known as EBC-46 has potential to slow down the rate of progression of the disease, which is a very aggressive form of cancer. However further investigation of the efficacy of EBC-46 for the treatment of DFTD is required before the results are scientifically conclusive.
The study was conducted by researchers from the Save the Tasmanian Devil Program’s veterinary pathology team in conjunction with an Australian biotechnology company, QBiotics, which provided the drug for the trial and contributed additional expertise.
EBC-46 is a highly potent molecule derived from the seed of a North Queensland rainforest plant. It has already shown promise in veterinary trials as an effective local treatment for a wide range of solid tumours in dogs, cats and horses. QBiotics is also currently investigating the application of EBC-46 for human use and is planning to commence clinical trials in the near future.
The pilot study on Tasmanian devils tested EBC-46 on the advanced primary DFTD lesions in four wild devils that were being held in captivity by the Program. The primary tumours in all four devils, which were injected directly with the compound, showed significant regression. Interestingly, the usually extensive metastatic disease associated with advanced DFTD, was not as widespread in two of the devils as would be expected for such an advanced stage of DFTD.
While the mode of action of EBC-46 is not fully understood at this stage, crucial to the drug’s efficacy is its ability to exploit the host’s response to disrupt the tumour blood supply and destroy tumour cells. This leaves surrounding healthy tissue virtually intact while destroying the tumour mass. Additionally, the tissue deficit left by the destruction of the tumour appears to undergo rapid and dramatic healing, including hair regrowth.
While EBC-46 is not a solution for the control and management of DFTD in the wild, it may have potential in slowing the rate of growth of the disease in captive animals. However, more detailed studies are required to qualify the effectiveness of the drug, particularly in reducing the rate of devil mortality associated with DFTD. The drug’s potential value to the Program is currently limited to treating infected devils held in captivity where a high degree of veterinary support can be provided. This may include females nursing pouch young and those animals of high genetic value who would ordinarily be euthanased due to the advanced stage of DFTD.
In the meantime, the Program is focused on priority conservation actions. These include the maintenance of the insurance population, which consists of well over 500 healthy devils – already representing 99 per cent of the genetic diversity of the species. Another strategy is to ensure the survival of the species in the wild by establishing populations of healthy devils in protected landscapes such as islands and peninsulas, which can be isolated from invasion by infected devils. The Program is also currently supporting important collaborative research into developing a possible vaccine for DFTD as a preventative measure for supporting on-ground conservation solutions.
Photo: Fruit of the blushwood tree growing in a plantation in far north Queensland, from which the molecule EBC-46 with anti-cancer properties has been derived by Australian drug company QBiotics