Tamper-resistant formula has seen a decline in total oxycodone injections since its listing on the PBS

Ever since OxyContin – or controlled-released oxycodone – was made available in Australia, uptake has been quite quick, Dr Briony Larance told delegates at the National Drug and Research Centre (NDARC) Symposium on Monday.

But with an increase in utilisation, “there has been an increase in concerns including with injection and related harms,” she says.

Dr Larance’s research into these harms on behalf of NDARC has seen some positive results for the introduction of reformulated OxyContin since its PBS listing on 1 April 2014.

Reformulated OxyContin is much harder to break down into an injectable substance, with a hydrogelling matrix that is harder to draw into a syringe, Dr Larance explains.

Her team analysed cohort data from November 2013 to September 2015 across NSW, Tasmania and SA, including indicators of opioid sales, drugs used at needle and syringe programs, opioid-related morbidity, help-seeking, treatment and mortality.

Data revealed a significant decline in the purchase of the original OxyContin product, with sales indicating that pharmacists are increasingly stocking reformulated OxyContin.

“There’s a clear preference for it in pharmacy… Pharmacists are preferring the tamper-resistant product,” Dr Larance told AJP.

While the original OxyContin 80mg tablets had quite high levels of injection, rates were found to be much lower for the reformulated OxyContin.

Analyses showed the reformulation led to a “large magnitude decline” in people attending injection centres for oxycodone.

There was no evidence of people switching to other brands such as Endone, said Dr Larance, and there was also “no evidence of people switching to more risky patterns of drug use.”

“We saw declines in both OxyContin and other brands in all our data,” she said.

The exception was an increase in Targin sales, “possibly offsetting the decrease in oxycontin,” said Dr Larance.

However, post introduction of reformulated OxyContin, the total injection of pharmaceutical opioids decreased overall.

Dr Larance points out that while it “can only make tampering or injection of opioids more difficult… this doesn’t mean the problem will go away,” 

She says there is still a need for broad services to tackle problem drug use and the physical harm that come with pill injection.

Dr Larance disclosed that her research was funded by an untied education grant from Mundipharma.