Winning breast cancer studies bring personalised approach to treatment

The new studies are all focused around personalised treatment, widely seen as the key to beating complex diseases like breast cancer, which has wide genetic variations. The winning studies are: personalised blood tests to monitor circulating tumour DNA and quickly determine whether treatment is working; a new antibody targeting hard-to-treat cancers; piloting a test to identify patients likely to suffer dangerous side-effects from a common existing treatment; and a genetic test to tell doctors which patients will benefit from an expensive new drug.

“With this funding round, we insisted that applicants should show how patients might benefit from the study sooner rather than later, plus how they plan to build on previous studies, whether in breast cancer or other areas,” said Evangelia Henderson, chief executive at the NZBCF. “We owe it to patients and to our donors to get real-world benefit from research whenever possible, and to maximise the investment that we and other charities have made over the years.”

Researchers were asked to submit applications aligned with the NZBCF’s priorities, including treatment for advanced breast cancer, improved clinical practice, and advances in genomic testing. The four funded studies, which bring the NZBCF’s total investment in research over the past two years to $2.5 million, are:

A clinical study using personalised blood tests to monitor tumour DNA – Prof Parry Guilford, University of Otago

Patients with advanced breast cancer usually go through multiple drug treatments as their disease worsens, and finding out whether a drug is working involves expensive, infrequent scans. Professor Parry Guilford’s clinical study, involving 50 patients with advanced breast cancer, will use a blood test to measure circulating tumour DNA (ctDNA). The test, which is inexpensive and can be done frequently, will be personalised to the genetic profile of each patient’s cancer and has the potential to detect small changes in tumour size which will indicate whether a cancer is growing or shrinking.

“ctDNA could provide faster feedback to patients and doctors, so that minimal time is wasted on treatments that aren’t working,” said Dr Guilford.

A new antibody targeting hard-to-treat cancers – Dr Dongxu Liu, Auckland University of Technology

In a recent project funded by the NZBCF, Dr Liu and his team identified a monoclonal antibody that targets a protein called SHON, commonly found in breast tumours that are resistant to treatment. Now, Dr Liu will test whether this antibody will prevent tumour growth in human cancer cells. The ultimate aim is clinical trials in breast cancer patients.

“Past funding from the NZBCF has supported us to the current stage, where we know that SHON plays a part in the growth of many cancers that are resistant to treatment,” said Dr Liu. “It’s exciting to have funding confirmed for the next stage, bringing us closer to testing a new drug in the patients that need it.”

Piloting a test to identify patients who will suffer severe side-effects on capecitabine – Assoc Prof Nuala Helsby, University of Auckland

Capecitabine is usually the first treatment women with advanced breast cancer receive. Unfortunately, 5-10% of patients on capecitabine experience dangerous side-effects, which can include blistering or severe pain in the hands and feet, diarrhoea, and can even cause death.

Patients who suffer these side-effects are deficient in the liver enzyme which removes the capecitabine from the bloodstream. This same enzyme also removes thymine from the bloodstream, so Professor Helsby and her team have developed a test where they give patients thymine, measure how much is removed from the bloodstream, and use that data to figure out whether they’re deficient in this important enzyme.

Prof Helsby’s team is already testing this procedure in gastrointestinal cancers, will now extend it to include advanced breast cancer patients at Auckland Hospital.

“Capecitabine is a very valuable treatment, but it isn’t right for all patients,” said Prof Helsby. “If we can determine which patients will suffer severe side-effects before they take the drug, we’ll spare them a huge amount of discomfort, possibly even life-threatening toxicity, and be able to prescribe them a treatment that they’ll tolerate.”

A genetic test to determine which HER2+ breast cancer patients will benefit from Kadcyla – Francis Hunter, University of Auckland

A new drug called Kadcyla has been approved for treatment of advanced HER2+ breast cancer. In clinical trials, 44% of tumours shrank when treated with Kadcyla, and on average, patients survived seven months longer – a huge gain for anyone facing a terminal illness.

In New Zealand, Kadcyla is approved for use but not publicly funded. Dr Hunter and his team will develop a new test to identify genes that control a patient’s response to Kadcyla, telling doctors who will benefit and who won’t. For advanced breast cancer patients, whose condition is incurable, it’s vital not to waste time on drugs that aren’t slowing their disease down.

“Personalised medicine – pairing patients with the most effective treatment for them specifically – will improve cancer treatment in the coming years,” said Dr Hunter. “Thanks to NZBCF funding, our work could benefit patients by ensuring they get the right treatment, and benefit the public by ensuring that expensive pharmaceuticals are used in a cost-effective way.”