The Food and Drug Administration has approved new labeling for Pfizer’s Embeda extended-release capsules, an opioid pain reliever that combines morphine with naltrexone to discourage drug abuse.
When taken properly, Embeda relieves pain by releasing only the morphine in the capsule. But when the capsule is crushed, the naltrexone in Embeda blocks some of the euphoric effects of the morphine and can trigger withdrawal in persons dependent on opioids.
The updated label states that Embeda is expected to reduce abuse when it is crushed and taken orally or snorted. It is the third extended release opioid to be approved by the FDA with labeling that describes the drug’s abuse-deterrent properties.
“More than one-third of extended-release opioids prescribed are morphine, and Embeda is the first extended-release morphine with the potential to reduce abuse via the oral and intranasal routes when crushed,” said Dr. Steven Romano, senior vice president of Pfizer’s Medicines Development Group.
Embeda was first approved by the FDA in 2009, but was voluntarily withdrawn from the market in 2011 after tests found “stability concerns” in the manufacturing process. Those issues were resolved in 2013.
Embeda was first evaluated in a clinical trial of 547 osteoarthritis patients. Additional studies found that crushed Embeda was less attractive to abusers and less likely to produce a “high” than morphine alone.
Still unclear, however, is whether the abuse-deterrent properties of Embeda will discourage abusers from liquefying the drug and taking it intravenously. The FDA is requiring a post-marketing study of that possibility.
“The science behind developing prescription opioids with abuse-deterrent properties is still evolving and these properties will not completely fix the problem. But they can be part of a comprehensive approach to combat the very serious problem of prescription drug abuse in the U.S.,” said Sharon Hertz, MD, acting director of the FDA’s Division of Anesthesia, Analgesia, and Addiction Products.
Embeda is indicated for the management of pain severe enough to require daily, around-the-clock, long-term opioid treatment and for which alternative treatment options are inadequate. Pfizer expects Embeda will be available in the U.S. in early 2015.
Common side effects of Embeda may include constipation, nausea, vomiting, stomach pain, drowsiness, dizziness, and headache.
“Prescription opioids are an important treatment option for people with chronic pain. However, misuse and abuse of opioids in the U.S. is a serious societal concern, which is why the development of abuse-deterrent formulations of these medicines is a high priority,” said Bob Twillman, PhD, Director of Policy and Advocacy for the American Academy of Pain Management. “All opioid medications, including morphine products, have the potential for abuse. We believe that anything that can be done to reduce this risk is a significant development for healthcare providers and their patients.”