World-first Australian pharmacogenetics trial for childhood cancer
A new trial will analyse the benefits of pre-emptive pharmacogenetic (PGx) screening in a cohort of patients aged 0-18 years who have either newly diagnosed cancer or who require bone marrow transplantation. Commencing this week, the trial will assess whether there is a decline in adverse drug reactions following PGx screening in the 0-18 age group, and could ultimately change the way that childhood cancer is treated, nationwide.
Associate Professor Rachel Conyers, Paediatric Oncologist at Murdoch Children’s Research Institute announced the launch of the trial, which will use the gold standard randomised controlled trial approach, during Pathology Update 2023.
“The trial will include individuals under the age of 18 who have a new cancer diagnosis or who are having a bone marrow transplant. The participants of the trial must also be taking a medication which is likely to have a dose change and is in the international guidelines for PGx. We aim to prove that, in the cancer population, there is a reduction in adverse drug reactions following PGx screening.
“This trial is important because how you respond to medications changes, particularly between the age of 0-5. These patients also don’t have as many comorbidities, health illnesses, or medications as adults. This trial is also unique in the sense that adverse medication reactions are self-reported by the patient or parent using National Cancer Institute Ped-PRO-CTCAE surveys. Pharmacists then do the formal grading in semi-structured interviews. There has been a similar trial carried out in adults in Europe, but this is the first of its kind in the 0-18 age group,” said Associate Professor Conyers.
In Australia, adverse drug reactions account for 30% of hospital admissions and cost the healthcare system $1.4 billion per annum. Evidence shows that 60% of paediatric oncology patients experience adverse drug reactions during cancer treatment, of which 20% are severe or life threatening. Importantly, 75% of adverse drug reactions reported in paediatric patients are preventable through greater pharmacovigilance and PGx testing.
In PGx, genomic information is used to study an individual’s response to drugs. These test results then help the doctor to choose the safest and most effective drug and dose which provides the opportunity to offer individualised cancer therapy. The trial is focussed on supportive care medications used in cancer therapy such as medications used for pain relief, anti-vomiting medications and medications that protect against bacterial and fungal infections.
“PGx testing has changed a lot over the years. We have gone from single gene assessment to small panels, to whole exomes and now whole genomes. Funding those approaches has not been well thought out or implemented. Currently, there is no hospital-based funding for PGx testing. Implementing it is therefore difficult when it is not possible to get a reimbursement.
“Other countries are ahead of us in this area. There has been a huge push to start implementing and using PGx in a more structured way in Australia and the RCPA is currently leading an initiative to create new guidelines, along with a framework for applications to the Medical Services Advisory Committee (MSAC) for PGx testing. However, there are still barriers to overcome, including lack of consumer and physician understanding, complex reporting, funding, pharmacist training and integration into the electronic medical record. As a result, we will also incorporate an extensive consumer and health practitioner informed education program to address the lack of understanding in this area.
“We will assess cost effectiveness by using inpatient and outpatient admissions and prescribing information from Services Australia and data linkage groups. If the benefits of pre-emptive PGx screening are proven in this trial, there will be an opportunity to provide the analysis nationally, repurposing whole genome sequencing which is currently used for every child diagnosed with cancer, and modifying it with PGx analysis,” said Associate Professor Conyers.