The FDA said it is not ready to banish non-abuse-deterrent opioid formulations from the market: “We have said that a class-wide requirement is not feasible or in the interests of public health at this time,” the agency wrote in a Federal Register notice.
It said it will continue to take a case-by-case approach to approval “with a goal of incentivizing an incremental, sponsor-driven market transition from conventional opioid formulations to formulations with meaningful abuse-deterrent properties.”
So far, only three opioid products on the market have approved abuse-deterrent labeling. Two of those, reformulated OxyContin (oxycodone) and Targiniq (oxycodone/naloxone), are from Purdue Pharma.
The other is from Pfizer, which won approval of abuse-deterrent Embeda, a combination of morphine and the opioid antagonist naltrexone, earlier this month.
In 2013, the FDA blocked generic versions of Purdue’s non-abuse-deterrent formulation of OxyContin, noting that the reformulation demonstrated efficacy in reducing abuse — allowing for the company to put abuse-deterrent labeling on the product.
Then in July, the FDA approved the company’s Targiniq that won abuse-deterrent labeling. Purdue, however, has not yet launched that product.
FDA has signaled that it is interested in the concerns of both branded and generic opioid manufacturers and held two separate conference calls in August asking each industry to select representatives to give presentations during both days of the meeting.
Only 1 month after FDA put the lid on OxyContin generics, the agency said Endo Pharmaceuticals’ reformulated Opana did not meet abuse-resistant criteria, and generic formulations of its original version were allowed on the market.
At that time, the agency said that these “seemingly paradoxical decisions were based on FDA’s determination that OxyContin was withdrawn by the manufacturer on the basis of safety concerns, whereas Opana was withdrawn for other, unspecified reasons.”
An experimental opioid drug designed to alleviate acute pain without the risk of abuse or addiction has “enormous” potential to treat some types of chronic pain, according to pain management experts.
The injectable analgesic – which for now has clunky name CR845 – was developed by Cara Therapeutics (NASDAQ: CARA), a Connecticut biopharmaceutical company. The company recently released the results of human abuse liability studies of CR845 on recreational drug users — who gave it very low scores for drug “liking” and making them feel “high.”
Unlike other narcotics, CR845 doesn’t act on opioid receptors in the brain and central nervous system – which can cause side effects such as respiratory depression, nausea, vomiting, and the euphoria that can lead to abuse and addiction. Instead, CR845 acts on receptors in nerve endings – in what is known as the peripheral nervous system
Cara Therapeutics hopes to begin Phase III clinical studies on CR845 in early 2015. If those efficacy studies are successful and it gets FDA approval – which could take years – the drug is most likely to be used as an injectable analgesic to treat acute pain caused by injuries or surgery.
“Initially this is going to be hospital based, for emergency rooms or acute care. But if it is effective as an analgesic, because of the low abuse potential this would be an enormous opportunity to (use) a safer, more effective analgesic that would avoid some of the rewarding properties of the current opioids. I would hope they would develop it.”
it most likely won’t be effective treating spinal pain or other types of chronic pain that originate in the central nervous system.
But even if CR845 is only approved for acute pain, Twillman says it could be a major step forward in reducing the risk of opioid addiction
Pfizer’s combination of morphine and naltrexone (Embeda) will be the third opioid painkiller to win the FDA’s abuse-deterrent label, the agency announced in a press release.
FDA said data have shown that the combination should reduce abuse when the drug is crushed and then eaten or snorted. When the tablet is crushed, the naltrexone — an opioid antagonist — blocks the euphoric effects of morphine.
The drug first came on the market in August 2009 but was voluntarily withdrawn in 2011 due to stability concerns. It came back on the market in November 2013, and can now add the abuse-deterrence claim.
A date for the release of the final guidance has not yet been set.