Pharmacokinetic (PK) Evaluation of Nalmefene Formulations

A Phase 1, Open Label, Randomized, Single Dose, Three-Period Crossover Study in Healthy Subjects to Compare the Pharmacokinetic Profiles of Nalmefene Following Administration of Intravenous and Intramuscular Nalmefene 0.5 mg (0.94% MgCl2) and Intravenous Nalmefene Hydrochloride Injection 0.5 mg

This study is designed to characterize the PK of nalmefene following IV bolus and IM injections using nalmefene 0.5 mg (0.94% MgCl2) and IV bolus of 0.5 mg nalmefene hydrochloride injection in healthy subjects.

Study Overview

• Status: Completed
• Conditions: Opioid Overdose
• Intervention / Treatment: Drug: Nalmefene + 0.94% MgCl2; Drug: Nalmefene + 0.94% MgCl2; Drug: Nalmefene Hydrochloride Injection

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Columbus, Ohio, United States, 43212
      • Ohio Clinical Trials

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Key Inclusion criteria:

1. Participants who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and cardiac monitoring.
2. Body weight ranging from 50 to 100 kg (110-220 lbs) inclusive at screening and body mass index (BMI) within the range [18.0-30.0] kg/m2 (inclusive).
3. Willing to be compliant with the protocol, are able to read, understand, and answer verbal questions.

Key Exclusion criteria:

1. Females who are pregnant or lactating.
2. Current or recent (within 5 years) history of drug or alcohol abuse.
3. History or any current conditions that might interfere with drug absorption, distribution, metabolism or excretion.
4. Known allergy or hypersensitivity to nalmefene hydrochloride or any of the excipients or other drug product components of nalmefene hydrochloride.
5. Dosing in a clinical drug study during the 30 days preceding the initial dose in this study.
6. Any significant illness during the 30 days preceding the initial dose in this study

Other inclusion/exclusion criteria may apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Treatment A; Nalmefene + 0.94% MgCl2 (IV)	Drug: Nalmefene + 0.94% MgCl2; Nalmefene 0.5 mg + 0.94% MgCl2 for IV (bolus) administration; Drug: Nalmefene + 0.94% MgCl2; Nalmefene 0.5 mg + 0.94% MgCl2 for IM administration
Experimental: Treatment B; Nalmefene + 0.94% MgCl2 (IM)	Drug: Nalmefene + 0.94% MgCl2; Nalmefene 0.5 mg + 0.94% MgCl2 for IV (bolus) administration; Drug: Nalmefene + 0.94% MgCl2; Nalmefene 0.5 mg + 0.94% MgCl2 for IM administration
Active Comparator: Treatment C; Nalmefene Hydrochloride injection	Drug: Nalmefene Hydrochloride Injection; Nalmefene Hydrochloride Injection 0.5 mg for IV (bolus) administration

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Area Under the Curve (AUC0-2.5)	Partial area under the plasma concentration-time curve from time zero to 2.5 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	2.5 minutes post-dose
Area Under the Curve (AUC0-5)	Partial area under the plasma concentration-time curve from time zero to 5 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	5 minutes post-dose
Area Under the Curve (AUC0-10)	Partial area under the plasma concentration-time curve from time zero to 10 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	10 minutes post-dose
Area Under the Curve (AUC0-15)	Partial area under the plasma concentration-time curve from time zero to 15 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	15 minutes post-dose
Area Under the Curve (AUC0-20)	Partial area under the plasma concentration-time curve from time zero to 20 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	20 minutes post-dose
Area Under the Curve (AUC0-30)	Partial area under the plasma concentration-time curve from time zero to 30 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	30 minutes post-dose
Area Under the Curve (AUCt)	Area under the plasma concentration-time curve from time zero to the time of last measurable concentration following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	Up to 48 hours post-dose
Area Under the Curve (AUCinf)	Area under the plasma concentration-time curve from time zero to infinity following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	Up to 48 hours post-dose
Maximum Plasma Concentration (Cmax)	Maximum plasma concentration of nalmefene following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene hydrochloride injection 0.5 mg IV bolus administration	Up to 48 hours post-dose
Area Under the Curve (AUC0-2.5)	Partial area under the plasma concentration-time curve from time zero to 2.5 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	2.5 minutes post-dose
Area Under the Curve (AUC0-5)	Partial area under the plasma concentration-time curve from time zero to 5 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	5 minutes post-dose
Area Under the Curve (AUC0-10)	Partial area under the plasma concentration-time curve from time zero to 10 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	10 minutes post-dose
Area Under the Curve (AUC0-15)	Partial area under the plasma concentration-time curve from time zero to 15 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	15 minutes post-dose
Area Under the Curve (AUC0-20)	Partial area under the plasma concentration-time curve from time zero to 20 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	20 minutes post-dose
Area Under the Curve (AUC0-30)	Partial area under the plasma concentration-time curve from time zero to 30 minutes following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	30 minutes post-dose
Area Under the Curve (AUCt)	Area under the plasma concentration-time curve from time zero to the time of last measurable concentration following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	Up to 48 hours post-dose
Area Under the Curve (AUCinf)	Area under the plasma concentration-time curve from time zero to infinity following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	Up to 48 hours post-dose
Maximum Plasma Concentration (Cmax)	Maximum plasma concentration of nalmefene following nalmefene 0.5 mg (0.94% MgCl2) IV bolus administration and nalmefene 0.5 mg (0.94% MgCl2) IM administration	Up to 48 hours post-dose

Collaborators and Investigators

• Sponsor: Purdue Pharma LP

Study record dates

Study Major Dates

• Study Start (Actual): February 6, 2026
• Primary Completion (Actual): April 3, 2026
• Study Completion (Actual): April 3, 2026

Study Registration Dates

• First Submitted: April 15, 2026
• First Submitted That Met QC Criteria: April 15, 2026
• First Posted (Actual): April 21, 2026

Study Record Updates

• Last Update Posted (Actual): April 24, 2026
• Last Update Submitted That Met QC Criteria: April 21, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Narcotic-Related Disorders; Drug Misuse; Mental Disorders; Substance-Related Disorders; Chemically-Induced Disorders; Drug Overdose; Prescription Drug Misuse; Opioid-Related Disorders; Opiate Overdose; Inorganic Chemicals; Chlorine Compounds; Chlorides; Hydrochloric Acid; Magnesium Compounds; nalmefene; Magnesium Chloride
• Other Study ID Numbers: NAL1008

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No