Opioid Modulation and Neural Reward Activation in Healthy Adults

University of Colorado Denver (CU Denver)

Status and phase: Completed; Phase 2; Phase 1

Conditions: Opioid Use, Unspecified; Alcohol Drinking

Treatments: Other: Placebo; Drug: Naltrexone

Study type: Interventional

Funder types: Other

Identifiers

NCT04854551

21-2886

Details and patient eligibility

About

This is a double blind study of the effects of opioid antagonism on the brain's reward response. The investigators will recruit participants to undergo two scans, one on active medication and one on placebo. During the scan, the investigators will assess reward.

Full description

The study will employ a crossover design. The study will use the monetary incentive delay task during functional MRI to assess reward. This task presents participants with cues indicating whether they are playing to win $5, win $0, or to avoid losing $5. This task has been well-validated to elicit activation in a key reward response area of the brain called the ventral striatum.

Enrollment: 13 patients

Sex: All

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Between 18 and 35 years of age,
• Is a moderate drinker (i.e. consumes 1-14 drinks/week for males, or 1-7 drinks/week for females).

Exclusion criteria

• Non-drinker
• Positive result on urine drug screen or breathalyzer at the start of any study visit
• Inability to complete MRI (e.g. presence of ferromagnetic objects in body)
• Current use of medications that alter the hemodynamic response such as insulin
• History of trauma resulting in loss of consciousness longer than 15 minutes
• Currently taking opioid medications
• Pregnancy

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Triple Blind

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13 participants in 2 patient groups

Placebo, Then Naltrexone

Experimental group

Description:

Participants first received placebo capsules each day in a blister pack for 5 days. After a washout period of at least 3 days, they then received naltrexone capsules (matching placebo capsules) at 25mg/day for days 1 and 2 and then 50mg/day for days 3-5 for 5 days.

Treatment:

Other: Placebo

Drug: Naltrexone

Naltrexone, Then Placebo

Experimental group

Description:

Participants first received naltrexone capsules each day in a blister pack for 5 days. Days 1 and 2 were at 25mg/day, and days 3-5 were at 50mg/day. After a washout period of at least 3 days, they then received placebo capsules (matching naltrexone capsules) for 5 days.

Treatment:

Other: Placebo

Drug: Naltrexone