Retrospective Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Med Genet. Dec 20, 2023; 11(4): 39-50
Published online Dec 20, 2023. doi: 10.5496/wjmg.v11.i4.39
Clinical utilities and end-user experience of pharmacogenomics: 39 mo of clinical implementation experience in an Australian hospital setting
Rosalind Moxham, Andrew Tjokrowidjaja, Sophie Devery, Renee Smyth, Alison McLean, Darren M Roberts, Kathy H C Wu
Rosalind Moxham, Sophie Devery, Renee Smyth, Alison McLean, Kathy H C Wu, Clinical Genomics, St Vincent's Hospital, NSW, Sydney 2010, Australia
Rosalind Moxham, Andrew Tjokrowidjaja, Alison McLean, Darren M Roberts, Kathy H C Wu, School of Clinical Medicine, Faculty of Medicine and Health, University of New South Wales, NSW, Sydney 2031, Australia
Darren M Roberts, Clinical Pharmacology, Drug Health Services, Royal Prince Alfred Hospital, NSW, Sydney 2050, Australia
Kathy H C Wu, School of Medicine, University of Notre Dame Australia, NSW, Sydney 2010, Australia
Kathy H C Wu, Discipline of Genetic Medicine, University of Sydney, NSW, Sydney 2006, Australia
Author contributions: Moxham R and Tjokrowidjaja A recruited patients, collected and analysed data; Tjokrowidjaja A drafted the original research report and Moxham R drafted and prepared the manuscript for publication; Devery S, Smyth R and McLean A recruited patients, collected and analysed data; Roberts DM advised on clinician recruitment and data analysis; Wu KHC as the coordinating principal investigator was responsible for the study design and overall project supervision, manuscript editing and review; all authors contributed to manuscript revision, read and approved the submitted version.
Supported by Partially funded by St Vincent’s Health Australia Inclusive Health Program; Early Career Research Grant from Avant.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of St Vincent's Hospital Human Research (approval No. 2019/ETH12892).
Informed consent statement: Participants of this study were invited clinicians and patients whose consent was implied when they completed the electronic surveys sent to their email address. The Patient Information Sheet and the Clinician Information Sheet were imbedded into the online surveys.
Conflict-of-interest statement: We have no financial relationships to disclose.
Data sharing statement: The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Kathy HC Wu, Founder, FRACP, MBBS, MMed, Associate Professor, Clinical Genomics, St Vincent's Hospital, Translational Research Centre, No. 97-105 Boundary Street, Darlinghurst, NSW, Sydney 2010, Australia.
Received: June 28, 2023
Peer-review started: June 28, 2023
First decision: August 31, 2023
Revised: November 6, 2023
Accepted: November 30, 2023
Article in press: November 30, 2023
Published online: December 20, 2023
Research background

In Australia, the New South Wales Health Commission conducted an ‘Inquiry into the Management of Mental Healthcare Delivery’ in 2018 that identified under-utilisation of pharmacogenomics (PG) and recommended such testing as a key priority to improve clinical outcomes for mental health patients. In order to see wider uptake, one needs to identify barriers to and facilitators of PG adoption in Australia, as perceived by patients who have had testing and clinicians who care for these patients. Such data, which remain limited to date, will inform an implementation science approach to promote the systematic uptake of PG into routine practice.

Research motivation

PG-guided therapy has been shown to significantly enhance clinical outcomes in the field of mental health. Currently, two-thirds of patients with a major depressive disorder fail to achieve remission during the first treatment level; and many require multiple different medications sequentially on a trial-and-error basis. In addition, it has been shown that the odds of remission diminish with every additional medication trial-and-error iteration; and that a window of therapeutic opportunity for major depressive disorder appears to be within the first 2 sequential treatments. PG-guided pharmacotherapy, which aims at giving the right drug at the right dosage to the right person at the right intervention time, has the potential to enhance both patient outcomes and health cost savings in the Australian mental health system. Despite the evidence, Australia has been slow in adopting PG testing to guide therapy. To facilitate widespread clinical implementation of PG it is necessary to know and understand the attitudes and acceptability of PG, as well as the support and resource requirements, amongst potential end-users, including clinicians and patients. This information can contribute to the development of a model of care, enhance the feasibility and clinical utility of PG to ensure successful implementation of PG-guided pharmacotherapy into routine clinical care of patients with mental illness.

Research objectives

The objectives were to evaluate retrospective file data of patients participating in PG testing in Australia and to re-contact patients and their general practitioners (GPs)/clinicians to assess the impact of PG both on treatment options and patient/clinician reported outcomes.

Research methods

A retrospective audit was undertaken of the PG results of 100 patients who underwent testing as part of their routine clinical care between 1 August 2018 and 31 September 2021 at an Australian public hospital genetics service. Specifically designed and pilot-tested surveys were used to assess clinician knowledge, acceptability and perceived utility of PG in the care of patients and evaluate patients knowledge of PG results, as well as, how the PG has impacted their pharmaceutical care and overall mental and physical health. Data was analysed using descriptive statistics to summarise categorical data ascertained from the retrospective chart review where correlations were made between patient’s reported medication side effects/adverse drug reaction (ADR) and the drug-gene interaction (DGI) of the implicated medication. Categorical data from clinician and patient surveys were summarised in descriptive and numerical formats with bar graphs and tables.

Research results

Through an audit of 100 patients who have had PG testing at St Vincent’s Hospital Clinical Genomics Sydney, we found 67% of patients were taking a medication with an actionable DGI at the time of testing. The importance of our work is that via paired end-user surveys it highlighted dichotomous perspectives on PG between patients and their clinicians (psychiatrists, immunologists, neurologists, transplant physicians, clinical pharmacologists and GPs). Patients were generally in favour of the utility of PG on improving their medication experience, the perception of PG among clinicians who care for these patients was however reserved with hesitancy and/or skepticism. This suggests that the uptake of PG is likely to be driven by patients, and clinicians need to be prepared to provide information and guidance to their patients.

Research conclusions

Our research identifies barriers to the clinical implementation of PG and suggests strategic solutions that could be put in place to support a wider adoption in routine medical practice. The majority (70%) of our patient participants have discussed their PG results with their GP; and of those who had medication changes following testing, half of the respondents had their medications changed by their GP. These findings suggest the importance of primary care involvement in the wider adoption and implementation of PG in Australia.

Research perspectives

To date, economic studies have suggested that PG testing can be cost-effective and that the cost of testing could be offset by its cost-savings from reduced time wastage on medication trial-and-error iterations, enhanced therapeutic response, and mitigation of ADRs. Future studies that explore the cost implications of PG-informed prescription should capture data on, not only individual patients, but also the overall healthcare system, to inform public funding for mainstream implementation in Australia.