Some opioid users become addicted when using prescription medications for pain relief. Reformulating those drugs to make them harder to abuse would seem like an obvious countermeasure. But it isn't that easy, addiction expert Keith Humphreys, PhD, professor of psychiatry and behavioral sciences at Stanford said.
"Abuse-deterrent opioids have a mixed track record,” Humphreys told me in an email, citing the drugs Opana ER and OxyContin. Extended release Opana was reformulated to make it harder to crush and inhale. Unfortunately, the abuse-deterrent properties backfired, prompting some users to inject the drug via shared needles, fueling the spread of HIV and prompting the drug's recent removal from the market at the request of the U.S. Food and Drug Administration. On the other hand, reformulated OxyContin was partially successful, Humphreys told me.
In one step towards progress, this week the FDA held a two-day public hearing to discuss data and methods to assess the impact of opioids with abuse-deterrent properties. In anticipation of the hearing, Humphreys discussed abuse-deterrent opioids in a Wonkblog article in the Washington Post:
Pharmaceutical companies have several methods of designing abuse-deterrent opioids. Some of the protections are physical, making the drugs more difficult to grind into a powder that can be snorted or made into a liquid that can be injected. Others are chemical: The opioid buprenorphine is sometimes combined in a tablet with another drug known as naloxone. If the pill is crushed, the opioid is rendered inert by the naloxone and no longer causes a high.
In addition, companies that invest extra time and money into making "a harder-to-abuse version of their drugs typically sell fewer of their drugs, a positive for public health but a hit to their bottom line,” Humphreys wrote.
Abuse-deterrent opioids are also usually higher-priced than the original formulation, making them less desirable for patients. "As long as abuse-deterrent formulations are not mandatory for all opioids, a company that invests in the technology is likely to forfeit market share to its competitors," he said.
“FDA Administrator Gottlieb is making the opioid epidemic a priority,” Humphreys told me via email. And one strategy to chip away at the epidemic is to create incentives for companies to develop abuse-deterrent opioids.
"This week the National Academies released a report calling for opioids to be approved in part based on their effect on population public health effects," Humphreys explained. “That would create a strong incentive for companies to develop and disseminate abuse-deterrent features in all opioids and to make them more effective than the ones in use today."
But even if such a measure were in place, abuse-deterrent opioids won't solve the opioid crisis in America. "People could still become addicted to them even while following their prescriptions to the letter," Humphreys writes in his Wonkblog article, and users could always work around the abuse-deterrent features of the drugs simply by taking doses larger than prescribed.
In short, abuse-deterrent opioids could be improved, but even if they worked better and were more widely used, they're no magic bullet.
Previously: New money for opioid abuse welcomed to help uninsured, says Stanford’s Keith Humphreys, Overprescribing of opioids is not just limited to a few bad apples and Stanford addiction expert: “The country needs to spring into action” on heroin epidemic
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