Oxycodone, a medication that is prescribed for pain. (John Moore/Getty Images)

The Food and Drug Administration is ramping up scrutiny of anti-abuse features on opioid painkillers to try to determine if they actually do what they're intended to do.

On Tuesday, the agency announced a two-day public meeting that will focus on whether the agency has “the right information to determine whether these products are having their intended impact on limiting abuse and helping to curb the epidemic,” according to an accompanying statement by FDA Commissioner Scott Gottlieb.

The meetings, detailed in a Federal Register notice, are scheduled for July 10-11.

Gottlieb called abuse-deterrent formulations — protections such as special coatings or additives to blunt a drug's euphoric effects when the medication is manipulated — an important focus for the agency. But he said there is a gap in understanding whether “these products result in a real-world, meaningful decrease in the frequency and patterns of opioid misuse and abuse.” The FDA requires companies selling abuse-deterrent medications to conduct post-approval studies assessing their impact, but such studies are challenging, he added.

The move is the latest indication of the agency's intensified focus on the opioid epidemic, which Gottlieb promised to make his top priority during his Senate confirmation hearing in April. Last week, the FDA asked Endo Pharmaceuticals to withdraw its Opana ER from the market because of signs that abusers were injecting the painkiller. It was the first time the agency had made such a request based on concerns about the public health consequences of abuse.

In an issue paper released Tuesday, the FDA's Center for Drug Evaluation and Research said that determining the impact of abuse-deterrent formulations is difficult because many of the drugs are being taken illicitly, so comprehensive and reliable data can be hard to come by.

The FDA previously has cautioned that “abuse-deterrent” doesn't mean “abuse-proof.” It cannot prevent someone who is prescribed a medication from taking extra pills to get high, for example. And because the agency's goal is to ensure that opioids are available to relieve pain for patients who need them, the FDA acknowledges that it might be impossible to stop all abuse.

Respondents who took part in The Washington Post-Kaiser Family Foundation survey on long-term, opioid painkiller use share their experiences of living with pain. (Monica Akhtar,Erin Patrick O'Connor/The Washington Post)

The agency has done considerable work on abuse-deterrence issues. In 2015, it issued a guidance to industry on such measures, and it held a two-day hearing last fall to discuss the guidance. Yet officials have noted that the science of abuse deterrence is relatively new and that both the formulations and the methods for evaluating their effectiveness are rapidly changing.

The latest FDA moves come as some experts argue that the benefits of abuse-deterrent formulations have been overstated. In a recent essay in the New England Journal of Medicine, two internists at the Yale School of Medicine noted that a cottage industry has sprung up online to instruct people on how to tamper with supposedly abuse-deterrent products.

More important, wrote William Becker and David Fiellin, the issue shouldn't distract physicians from pursuing alternatives to treat pain, such as cognitive therapy and yoga. They noted that long-term opioid therapy often is not effective and that prolonged use can be harmful.

The Endo Pharmaceuticals drug is an example of an abuse-deterrent effort that was ineffective. The drug was approved in 2006 for moderate-to-severe pain and reformulated in 2012 with a gel coating designed to deter people from crushing and snorting it. But the FDA said last week that subsequent data showed a “significant shift” in abuse from people snorting the medication to injecting it.

Increased needle-sharing of Opana ER has been linked to serious blood-disorder cases in Tennessee in 2012 and a 2015 outbreak of HIV and hepatitis C in Indiana, officials said.

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