New Zealand cancer drugs being put to the test

Dr Francis Hunter says the Auckland team will use new genome editing technology. Photo / Doug Sherring

Two groundbreaking drugs developed in Auckland are being used to help scientists treat different types of cancer.

New Zealand scientists will be closely following and analysing the findings of a trial in the United States with a drug developed at the Auckland Cancer Society Research Centre, one of the world's leading anti-cancer laboratories.

Funding has been secured for a phase two trial of a cancer drug called PR-104 at the Cleveland Clinic in Ohio in the next year. Lab tests will be co-ordinated by the Fred Hutchinson Cancer Research Center in Seattle.

Auckland scientists will work with the Seattle team to see if it is possible to predict whether patients would benefit from the drug.

The study will involve patients with T-cell acute lymphoblastic leukaemia which has not responded to traditional treatments or has returned after standard treatment.

The disease is a rare form of leukaemia prevalent in children and young adults.

Research fellow Dr Francis Hunter said the trial involved patients who had "a very grim prognosis and only limited treatment options".

Hunter said the Auckland team would be using new genome editing technology which enabled scientists to make changes to the DNA of cells. This allowed them to make a direct link between specific mutations present in cancers and the response of that cancer to therapy.

Hunter said: "It's very useful to have an early understanding of the way the genetics of an individual cancer might influence how sensitive it is to that drug. It allows the subsequent development, once that drug reaches human clinical trials, to be much more scientifically targeted and more rational.

"There is widespread excitement among cancer researchers that the application of such novel technologies will be key to realising further gains toward reducing the burden of cancer in New Zealand."

Hunter said similar technology had been used to identify the enzyme inside tumour cells responsible for activating the pre-clinical compound SN30000, which the Auckland centre was developing.

"The clear implication of that discovery is that the drug would be best deployed or best targeted to patients whose tumours have very high activity of this particular enzyme."

The Auckland centre's director, Professor Bill Denny, said studying genetics was the key to cancer eventually becoming a chronic disease rather than a deadly one.

"What we do hope to do is to first of all make treatment much less toxic and secondly, to try and understand when a cancer comes back what is different -- how is the genome different, what are the driving mutations?

"Then, can we select compounds which will target those driving mutations and can we repeatedly keep the disease at bay as a chronic disease?

"We have all the other technology. Once we know what the target is we know how to drug it. It's finding the targets -- understanding which of 20,000 genes is the one that's most important for this particular tumour or this combination of changes in this particular tumour.

"That's the information that the drug designers need and genomics is the way to achieve that certainly."

Auckland's cancer drug

Tumours have a poor supply of oxygen so in 1979 Professor Bill Wilson and colleagues began to look into how to exploit that.

It took some years but they eventually made PR-104, a chemical which, in oxygen-starved tumours, releases nitrogen-mustard, an older form of cancer killer.

Human trials began in Hamilton and Auckland in 2006.

Cancer Research Week

The Cancer Society's Cancer Research Week starts on Mondayand runs until May 7.

It focuses on the ground-breaking and innovative medical research work being done locally and its relevance to all New Zealanders.

World renowned cancer researcher Emeritus Professor David (Herbie) Newell is the keynote speaker and is giving a public lecture, Cure for Cancer: Myth or Reality, at 6.30pm on May 3 at Domain Lodge, Grafton.