Stamford, Conn., March 17, 2022 – Purdue Pharma L.P. is accepting proposals for investigator-initiated research (IIR) to assess opioid overdose reversal in Emergency Department (ED) and Emergency Medical Service (EMS) settings. Because we recognize there is value in data derived from sources other than traditional clinical trials, the Company will provide support for select investigations that explore the real-world clinical safety and effectiveness of nalmefene hydrochloride injection, 2mg/2mL (1mg/1mL),1 alone, or in sequence with naloxone, for the treatment of known or suspected opioid overdose in ED/EMS settings.

Leading health officials, including the National Institutes of Health, have encouraged the development of ‘overdose-reversal and prevention interventions’ as part of a comprehensive approach to addressing the opioid crisis.2 In furtherance of this aim, the science would benefit from real-world data examining long-acting opioid overdose treatments and the role they may serve for the contemporary management of known or suspected opioid overdose,” said Monica Kwarcinski, PharmD, Vice President, Medical Affairs at Purdue Pharma. “This initiative aims to support researchers pursuing studies to help advance our knowledge and understanding of opioid overdose reversal in emergency medicine.”

Research conducted under the initiative will be independently developed and conducted by independent third-party investigators without the participation of the company, with funding and/or nalmefene hydrochloride injection, 2mg/2mL (1mg/1mL) provided by Purdue Pharma. Interested researchers must submit their Curriculum Vitae and a brief letter of intent outlining the study proposal via email to

Letters of intent will be accepted through March 31, 2022, at 5:00 p.m. ET. Additional information can be found on the Investigator-Initiated Research page of the Purdue Pharma website.

FDA recently approved Purdue’s abbreviated new drug application for nalmefene hydrochloride Injection, 2mg/2mL (1mg/1mL). Nalmefene is an opioid antagonist indicated for the complete or partial reversal of opioid drug effects, including respiratory depression, induced by either natural or synthetic opioids, and in the management of known or suspected opioid overdose.



Nalmefene hydrochloride injection is contraindicated in patients with a known hypersensitivity to the product.


Use of Nalmefene Hydrochloride injection in Emergencies

Nalmefene Hydrochloride injection, like all drugs in this class, is not the primary treatment for ventilatory failure. In most emergency settings, treatment with Nalmefene Hydrochloride injection should follow, not precede, the establishment of a patent airway, ventilatory assistance, administration of oxygen, and establishment of circulatory access.

Risk of Recurrent Respiratory Depression

Accidental overdose with long acting opioids [such as methadone and levo-alpha-acetylmethadol (LAAM)] may result in prolonged respiratory depression. Respiratory depression in both the postoperative and overdose setting may be complex and involve the effects of anesthetic agents, neuromuscular blockers, and other drugs. While Nalmefene Hydrochloride injection has a longer duration of action than naloxone in fully reversing doses, the physician should be aware that a recurrence of respiratory depression is possible, even after an apparently adequate initial response to Nalmefene Hydrochloride injection treatment.

Patients treated with Nalmefene Hydrochloride injection should be observed until, in the opinion of the physician, there is no reasonable risk of recurrent respiratory depression.

 Cardiovascular Risks with Narcotic Antagonists

Pulmonary edema, cardiovascular instability, hypotension, hypertension, ventricular tachycardia, and ventricular fibrillation have been reported in connection with opioid reversal in both postoperative and emergency department settings. In many cases, these effects appear to be the result of abrupt reversal of opioid effects.

Although Nalmefene Hydrochloride injection has been used safely in patients with pre-existing cardiac disease, all drugs of this class should be used with caution in patients at high cardiovascular risk or who have received potentially cardiotoxic drugs

 Risk of Precipitated Withdrawal

Nalmefene Hydrochloride injection, like other opioid antagonists, is known to produce acute withdrawal symptoms and, therefore, should be used with extreme caution in patients with known physical dependence on opioids or following surgery involving high doses of opioids. Imprudent use or excessive doses of opioid antagonists in the postoperative setting has been associated with hypertension, tachycardia, and excessive mortality in patients at high risk for cardiovascular complications.

 Incomplete Reversal of Buprenorphine

Preclinical studies have shown that nalmefene at doses up to 10 mg/kg (437 times the maximum recommended human dose) produced incomplete reversal of buprenorphine-induced analgesia in animal models. This appears to be a consequence of a high affinity and slow displacement of buprenorphine from the opioid receptors. Hence, Nalmefene Hydrochloride injection may not completely reverse buprenorphine-induced respiratory depression.


The most common adverse reactions (>1%) reported in clinical trials with nalmefene injection were nausea (18%), vomiting (9%), tachycardia (5%), hypertension (5%), postoperative pain (4%), fever (3%), and dizziness (3%).

To report SUSPECTED ADVERSE REACTIONS, contact Purdue Pharma L.P. at 1-888-726-7535 or FDA at 1-800-FDA-1088 or www​.fda​.gov/​m​e​d​watch.

Please read Prescribing Information available here.

For more information, visit www​.nalmefenehcl​.com.

 About Purdue Pharma L.P.

Purdue Pharma and its subsidiaries develop, manufacture and market medications and consumer health products to meet the evolving needs of healthcare professionals, patients, consumers and caregivers.

Purdue’s plan of reorganization will deliver billions in value to communities across the country to fund programs specifically for abatement of the opioid crisis. The bankruptcy settlement will also deliver funds to private abatement trusts for the benefit of personal injury claimants.

Substantially all of Purdue’s assets will be transferred to a new post-emergence company with a public-minded mission. This new company will be governed by new independent board members, and will operate in a responsible and sustainable manner taking into account long-term public health interests relating to the opioid crisis. The company will continue serving patients and consumers who rely on its medicines and products, pursuing its pipeline, and introducing medicines that will help save and improve lives.

Media Contact:

Michele Sharp

(203) 588-7584

# # #


  1. Nalmefene Hydrochloride Injection 2mg/2mL (1mg/1mL) [Full Prescribing Information]. Stamford, CT: Purdue Pharma L.P., 02/08/2022. https://​www​.accessdata​.fda​.gov/​s​p​l​/​d​a​t​a​/​d​4​b​b​0​7​9​7​-​a​4​e​d​-​4​e​d​4​-​9​9​0​4​-​6​0​4​4​3​3​e​e​a​4​f​f​/​d​4​b​b​0​7​9​7​-​a​4​e​d​-​4​e​d​4​-​9​9​0​4​-​6​0​4​4​3​3​e​e​a​4​f​f.xml. Accessed February 21, 2022.
  2. Volkow N, Collins F. The Role of Science in Addressing the Opioid Crisis. N Engl J Med 2017;377(4):391-394.

Privacy Policy Updates

Please read carefully the Purdue Pharma L.P. Privacy Policy (the “Privacy Policy”), which is part of the Purdue Pharma L.P. Terms and Conditions, before you access, download, or otherwise use any of our websites, related other parties’ websites, mobile applications, or any electronic service (collectively, the “Service”). This Privacy Policy describes the information collected through Your use of the Service, how we use it, how we share it, how we protect it, and the choices You can make about Your information.