New bowel cancer therapy up for subsidy

Australians with advanced bowel cancer may soon get subsidised access to a drug that only works on people with a specific genetic make-up.

The drug, called Erbitux, is one of a growing number of targeted cancer therapies like the breast cancer treatment Herceptin that benefit patients with particular types of genes.

Drug company Merck Serono is applying to have the medication funded through the Pharmaceutical Benefits Scheme (PBS) for patients with late-stage disease who have failed on other treatments.

The treatment slows tumour growth allowing sufferers to live longer, but is not a cure.

It has been rejected for subsidy twice on the grounds it was not cost effective, but Australian scientists have since helped discover a key marker which explains why it works in some patients and not others.

It is only effective in the two-thirds carrying the normal or "wild" form of the gene, called K-ras.

A test to detect a patient's K-ras status is funded by Merck.

Dr Nick Pavlakis, an oncologist at Royal North Shore Hospital in Sydney, said the drug works by directly targeting the mechanism in the body that causes uncontrolled cell growth and cancer proliferation.

"Because of the identification of the K-ras biomarker, we can more accurately predict which patients will most likely respond best to therapy and therefore personalise their treatment," Dr Pavlakis said.

"All patients who are in this disease setting should have access to all available therapeutic support. Erbitux is an important development for these patients."

Professor Ian Olver, chief executive of Cancer Council Australia, said targeted therapies were the way of the future in cancer care.

"This is the ideal situation where, rather than giving a drug to everyone, we can actually target it to patients that are more likely to respond," Prof Olver said.

"With a major disease like bowel cancer there are significant savings to be made if you can be more precise about who gets the drug."

A study released at a US cancer conference in June showed patients with the normal form of the gene had a 32 per cent lower risk of disease progression when Erbitux was added to standard chemotherapy.