New cancer therapies for patients suffering from hard-to-treat cancers are being developed following a major discovery by Australian scientists.

Australian scientists have found a way to "starve" cancer cells, providing hope for new drug treatments for some of the most aggressive forms of the disease.

Scientists at Sydney's Centenary Institute of Cancer Medicine have teamed up with the CSIRO to develop a drug that would work by blocking the metabolic process critical to cancer cells and their growth.

Clinical trials will likely begin within three years and were made possible following an "exciting" breakthrough in the understanding of the biology of cancer.

A study, led by Associate Professor Jeff Holst at the Centenary Institute, discovered that certain cancer cells rely on the amino acid glutamine to survive and grow.

Unlike normal cells, pumps found on cancer cells are used to feed off the glutamine found in healthy cells, said Ass Prof Holst.

"If we are able to specifically block the supply of nutrients to cancer cells by inhibiting the function of this protein, we can essentially 'starve' the cells and stop them from growing, he said.

The team also identified molecules that block the action of the protein and these are now being developed as possible new drugs.

Ass Prof Holst said this 'novel' approach works particularly well on hard-to-treat cancers like triple negative breast cancer that can currently only be treated with chemotherapy.

The new therapy will be developed by a privately held biotechnology company called MetabloQ Pty Ltd.