A Study of [14c]-Samidorphan (Also Known as ALKS 33) in Healthy, Male Volunteers

A Single-Center, Open-Label Study to Evaluate the Absorption, Metabolism, and Excretion of Single Doses of [14c]-Samidorphan in Healthy Male Subjects

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02504463

Enrollment

Registered

2015-07-22

Start date

2015-06-30

Completion date

2015-09-30

Last updated

2015-09-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy

Keywords

Alkermes, Samidorphan, ALKS 33, Healthy Volunteer, Pharmacokinetics

Brief summary

This study will determine the pharmacokinetics (PK) of \[14c\]-samidorphan in healthy male volunteers.

Interventions

DRUGSamidorphan IV

Single IV administration

DRUG[14c]-Samidorphan sublingual

Single sublingual administration containing radiolabel

DRUG[14c]-Samidorphan oral

Single oral administration containing radiolabel

Study design

Allocation

NON_RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

MALE

Age

18 Years to 55 Years

Healthy volunteers

Yes

Inclusion criteria

* Body mass index (BMI) of greater than/equal to 19 and less than/equal to 32 kg/m\^2 at screening (minimum weight of 50.0 kg) * Generally good health * Subjects must agree to reduce the risk of a female partner becoming pregnant during the study and for 30 days after the last dose of the study drug by abstinence from heterosexual relationships or use of a reliable contraceptive method * Additional criteria may apply

Exclusion criteria

* Clinically significant illness within 30 days * History of alcohol or opioid dependence, or positive urine toxicological screen for marijuana, cocaine, amphetamines, opioids, barbiturates, and benzodiazepines * History of oral or gastrointestinal disease * Irregular bowel or bladder function * History of allergy or hypersensitivity to opioid medications or opioid antagonists (eg, naltrexone, naloxone) * Current or pending legal charges or probation that would interfere with study conduct * Use of alcohol within 24 hours prior to admission or urine positive test for alcohol at screening or admission * Tobacco or nicotine use within 90 days * Anticipated need for prescription medicines during the study period * Additional criteria may apply

Design outcomes

Primary

Measure	Time frame	Description
AUC 0-t	Up to 120 hours after each dose	Area under the concentration time curve of total radioactivity from time 0 to last observed concentration in blood and plasma
Cmax	Up to 120 hours after each dose	Maximum concentration of total radioactivity in blood and plasma
Tmax	Up to 120 hours after each dose	Time to maximum concentration of total radioactivity in blood and plasma
Fe%0-t	Up to 120 hours after each dose	Fraction of dose excreted in urine and feces

Secondary

Measure	Time frame
Safety and tolerability will be measured by the incidence of Adverse Events	Up to 35 days

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026