Pharmacokinetic Evaluation of Intranasal Nalmefene Using Three Dosing Regimens

Inclusion Criteria: * Male or female aged 18 to 55 years inclusive * BMI ranging from 18 to 30 kg/m2, inclusive * Adequate venous access * Subjects must be non-smokers * On screening and admission, the following standards had to be met before dosing and were permitted to be repeated once: * Systolic blood pressure: 140 mmHg or less and equal to or greater than 90 mmHg * Diastolic blood pressure: 90 mmHg or less and equal to or greater than 55 mmHg * Heart rate: 100 beats per minute (bpm) or less and equal to or greater than 40 bpm * Respiratory rate: 20 respirations per minute (rpm) or less and equal to or greater than 8 rpm Exclusion Criteria: * History of clinically significant disease * Significant trauma injury, major surgery, open biopsy within 30 days prior to screening * Following an abnormal diet 4 weeks prior to screening * Use of prescribed or over the counter medications, dietary supplements, herbal products, vitamins or opioid analgesics 14 days before intervention and throughout the study * Use of enzyme altering drugs 30 days before intervention or during the study * Use of nasal products 28 days before intervention and throughout the study * Experimental agents used at least 8 weeks prior to initial dosing for a period equivalent to 5 half-lives of the agent (whichever was longer). * Positive urine drug test for alcohol, opioids, cocaine, methamphetamine, benzodiazepines, tetrahydrocannabinol (THC), barbiturates, or methadone at screening or admission. * Previous or current opioid, alcohol, or other drug dependence (excluding nicotine and caffeine) * Positive urine screen for cotinine (smoking and the use of tobacco products were not permitted for 4 weeks prior to the first dose of study drug and throughout the duration of the study). * An ECG QTcF interval \>450 msec for males and \> or equal to 470 msec for females. * Clinically significant concurrent medical conditions * Donated or received blood 30 days before intervention * Women who are pregnant or breastfeeding at screening and prior to each administration of study drug * Women of childbearing potential unless surgically sterile or use effective contraception * Male subjects of childbearing potential that do not agree to use effective contraception * Male subjects who plan to donate sperm or have female partner(s) who are pregnant, lactating or planning to attempt to become pregnant during the study or within 4 weeks after completion of the study * Positive test for HBsAg, HCVAb, or HIVAb at screening * Current or recent upper respiratory tract infection * Current or recent use of any decongestants * Allergic to nalmefene * Those who would not abstain from engaging in strenuous exercise during the inpatient stay of the study. * Those who would not abstain from consuming poppy seed or similar opium derived food stuff during the study. * Those who would not abstain from ingesting alcohol, drinks containing xanthine \>500 mg/day (e.g., Coca Cola®, coffee, tea, etc.), or grapefruit/grapefruit juice 72 hours before initial dosing and throughout the duration of the study. * Those deemed unlikely to be able to comply with the requirements of the protocol. * Those with any laboratory tests from samples taken at screening considered clinically significant. * Those with a known intolerance to continuous ECG lead adhesive exposure. * Brief Smell Identification Test (BSIT) score \< 5 at screening. * Those with a known hypersensitivity reaction to plastic.