e-Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2020

Patterns of oxycodone controlled-release use in older people with cancer following public subsidy of oxycodone/naloxone formulations: An Australian population‐based study (#295)

Ben Daniels 1 , Tim Luckett 2 , Simon Holliday 3 , Winston Liauw 4 , Melanie Lovell 5 , Jane Phillips 2 , Debra Rowett 6 7 , Toby Newton-John 8 , Hanna Tervonen 1 , Sallie-Anne Pearson 1
  1. Medicines Policy Research Unit, Centre for Big Data Research in Health, UNSW, Kensington
  2. IMPACCT, Faculty of Health, University of Technology Sydney, Ultimo, NSW, Australia
  3. School of Medicine and Public Health, Faculty of Health and Medicine, University of Newcastle, Newcastle
  4. Cancer Services, South Eastern Sydney Local Health District , Sydney
  5. Palliative Care, HammondCare, Greenwich, NSW, Australia
  6. School of Pharmacy and Medical Sciences, University of South Australia, Adelaide
  7. Drug and Therapeutics Information Service, Southern Adelaide Local Health Network, Adelaide
  8. Graduate School of Health, University of Technology Sydney, Ultimo, NSW, Australia

Aim
Public subsidy of the oxycodone/naloxone controlled-release (CR) combination in December 2011 expanded the overall market for oxycodone CR in the general public in Australia; we evaluate its impact in people with cancer.

Methods
We used Repatriation Pharmaceutical Benefits (RPBS) dispensing data linked with the NSW Cancer Registry for Department of Veterans’ Affairs healthcare card holders 65 years and older residing in NSW between 2004 – 2013 to identify clients with cancer and their opioid dispensings. We used interrupted time series analysis to model changes in monthly rates of oxycodone CR tablets dispensed and initiations. We performed a retrospective cohort study to examine changes in client characteristics and opioid utilisation over time by comparing clients initiating oxycodone CR before and after subsidy.

Results
The rate of oxycodone CR tablets dispensed/month increased by 20% from December 2011, due to uptake of the oxycodone/naloxone CR combination; monthly initiations increased immediately by 17%. Initiations of buprenorphine, fentanyl, and morphine declined from December 2011. DVA healthcare card holders were significantly more likely to initiate the 5 mg oxycodone CR formulation; more likely to use immediate-release oxycodone in the 90 days following initiation; and less likely to use a weak opioid in the 90 days preceding oxycodone CR initiation following December 2011 than they were prior to that time.

Conclusions
The public subsidy of the oxycodone/naloxone CR formulation expanded the overall oxycodone CR market for Department of Veterans’ Affairs healthcare card holders with cancer. Our findings highlight the need for updated guidelines around risk management for opioid treatment in patients with cancer.