On Aug. 7, the U.S. Food and Drug Administration approved Zurnai, the first nalmefene hydrochloride auto-injector for the emergency treatment of known or suspected opioid overdose in adults and pediatric patients 12 years of age and older. The agency approved the first nasal spray formulation of nalmefene in May 2023.
Drug overdose persists as a major public health issue in the U.S., with more than 107,000 reported fatal overdoses occurring in 2023, primarily driven by synthetic opioids like illicit fentanyl. Nalmefene and naloxone are two available options to reverse opioid overdose. The FDA has worked to increase availability and accessibility of both options to encourage harm reduction and reduce overdose death.
“The FDA remains focused on broadening access to opioid overdose reversal agents, including naloxone and nalmefene. Today’s approval adds a new nalmefene product and route of administration to support greater options for opioid overdose reversal,” said FDA Commissioner Robert M. Califf, M.D. “Since launching the FDA Overdose Prevention Framework in 2022, the agency continues to build upon efforts that address the overdose crisis currently impacting the nation.”
Nalmefene is an opioid receptor antagonist which is used to treat acute opioid overdose. If nalmefene is administered quickly, it can reverse the effects of opioid overdose, including respiratory depression, sedation and low blood pressure (hypotension). The newly approved product delivers 1.5 milligrams (mg) of nalmefene under the skin (subcutaneous) or into muscle (intramuscular). Zurnai is a single-dose, pre-filled auto-injector and is available only by prescription.
The approval of Zurnai is supported by safety and pharmacokinetic studies, as well as a study in healthy individuals who use opioids recreationally, to assess how quickly the product works. The most common adverse reactions are feeling hot, dizziness, nausea, headache, chills, vomiting, feeling pain from actions that aren’t typically painful such as lightly touching your skin (allodynia), palpitations, ringing or buzzing in the ear (tinnitus), ear discomfort, feeling abnormal, burning sensation, hot flush and irritability.
The use of nalmefene hydrochloride in patients who are opioid-dependent may result in opioid withdrawal characterized by the following signs and symptoms: body aches, diarrhea, fast heart rate (tachycardia), fever, runny nose, sneezing, goosebumps (piloerection), sweating, yawning, nausea or vomiting, nervousness, restlessness or irritability, shivering or trembling, abdominal cramps, weakness and increased blood pressure.
The FDA granted this application Fast Track and Priority Review designations, which expedite the development and review of drugs that have the potential to provide a significant improvement in the safety or effectiveness of the treatment, diagnosis or prevention of a serious condition.
The FDA granted approval of Zurnai to Purdue Pharma L.P.
The FDA’s Overdose Prevention Framework is the agency’s vision to undertake impactful, creative actions to prevent drug overdoses and reduce deaths. The framework consists of four priorities, including encouraging harm reduction through efforts to increase availability of and expand access to overdose reversal products.
