A Phase 2 interventional study of Naloxone and Placebo in Obesity, sponsored by University of California, San Francisco. Completed at 1 site in United States. Open to female participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2021-11-03.
Sponsored by University of California, San Francisco · Phase 2, Interventional, and Basic science
The purpose of this study is to understand how the opioid system is involved in eating behavior.
Obesity is associated with greater risk for cardiovascular disease (CVD), stroke, diabetes, and mortality, and is a heterogeneous condition with various causes and thus a diversity of intervention targets. Compulsive overeating afflicts 30% of people seeking obesity treatment and increases risk for CVD factors. This trial involves two participant visits to test whether opioid blockade (Day 1 or 2, depending on randomization), compared to placebo (Day 1 or 2, depending on randomization), will elicit common symptoms of opioid withdrawal, including nausea. Participants will receive each condition on separate days.
6,296 studies on the registry are indexed under Obesity; 1,692 are open to participants now.
This study's enrollment of 41 is below the median of 78 across 4,878 interventional studies indexed under Obesity.
Browse Obesity studies →University of California, San Francisco is the lead sponsor of 2,132 studies on the registry; 375 are open to participants now.
Of its 262 completed or terminated interventional studies of FDA-regulated products, 196 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
4 mg / 0.1 ml Naloxone at visit 1, followed by 0.1 ml saline (Placebo) at visit 2 (with a washout period in between the two visits)
Drug: Naloxone · Drug: Placebo
0.1 ml saline (Placebo) at visit 1, followed by 4 mg / 0.1 ml Naloxone at visit 2 (with a washout period in between the two visits)
Drug: Naloxone · Drug: Placebo
4 mg / 0.1 ml
Also known as: Narcan
0.1 ml
Also known as: saline
Number of Participants Who Reported Nausea at 10 Minutes Post Treatment
Dichotomized response on the "I feel nauseous" question of the Subjective Opiate Withdrawal Scale, at 10 minutes after the listed intervention (among participants who completed both intervention visits). Response 0 = absence of nausea, 1 = presence of nausea.
Time frame: 10 minutes post-treatment
Number of Participants Who Reported Nausea at 30 Minutes Post Treatment
Dichotomized response on the "I feel nauseous" question of the Subjective Opiate Withdrawal Scale, at 30 minutes after the listed intervention (among participants who completed both intervention visits). Response 0 = absence of nausea, 1 = presence of nausea.
Time frame: 30 minutes post-treatment
Cortisol
Geometric Mean Salivary Cortisol level.
Time frame: 25 minutes post-treatment
Cortisol
Geometric Mean Salivary Cortisol level.
Time frame: 55 minutes post-treatment
Subjective Opiate Withdrawal Scale
Summed score of Subjective Opiate Withdrawal Scale (SOWS). Scale consists of 16 items answered on a 5 point numeric rating scale. Score range is 0 (lesser withdrawal symptoms) to 64 (greater withdrawal symptoms). Scores were assessed at 10 minutes after Naloxone, and at a separate visit, 10 minutes after Placebo, among participants who completed both study visits.
Time frame: 10 minutes post-treatment
Subjective Opiate Withdrawal Scale (Abbreviated)
Mean score on subset of 5 items (which used a 5 point numeric rating response scale) from the Subjective Opiate Withdrawal Scale (SOWS). This summed score can range from 0 (corresponding to lesser withdrawal symptoms) to 20 (corresponding to greater withdrawal symptoms).
Time frame: 30 minutes post-treatment
Reward-Driven Eating Scale (RED)
Reward-Driven Eating Scale (RED) total score ranges from 0 (lower reward-driven eating) to 52 (higher reward-driven eating).
Time frame: Evaluated before study visit 1
Impulsivity (Delayed Discounting)
Impulsivity, measured by the Delayed Discounting cognitive task, based on a series of 30 computer-administered trials or questions. Indifference points (a measure of how much a person values a delayed reward) are determined for time delays of: 1 day, 7 days, 30 days, 180 days, and 365 days, and these are used to calculate an Area Under the Curve which ranges from 0 to 1 (lower numbers indicate higher impulsivity) as a metric of probability.
Time frame: Impulsivity was assessed before the study visit 1 intervention.
| Milestone | Experimental: Naloxone, Then Placebo | Experimental: Placebo, Then Naloxone |
|---|---|---|
| Started | 23 | 18 |
| Completed | 23 | 18 |
| Not completed | 0 | 0 |
| Milestone | Experimental: Naloxone, Then Placebo | Experimental: Placebo, Then Naloxone |
|---|---|---|
| Started | 23 | 18 |
| Completed | 20 | 18 |
| Not completed | 3 | 0 |
| Withdrew: Lost to follow-up | 3 | 0 |
| Milestone | Experimental: Naloxone, Then Placebo | Experimental: Placebo, Then Naloxone |
|---|---|---|
| Started | 20 | 18 |
| Completed | 20 | 18 |
| Not completed | 0 | 0 |
Dichotomized response on the "I feel nauseous" question of the Subjective Opiate Withdrawal Scale, at 10 minutes after the listed intervention (among participants who completed both intervention visits). Response 0 = absence of nausea, 1 = presence of nausea.
| Participants | Naloxone | Placebo |
|---|---|---|
| Number of Participants Who Reported Nausea at 10 Minutes Post Treatment | 17 | 18 |
Dichotomized response on the "I feel nauseous" question of the Subjective Opiate Withdrawal Scale, at 30 minutes after the listed intervention (among participants who completed both intervention visits). Response 0 = absence of nausea, 1 = presence of nausea.
| Participants | Naloxone | Placebo |
|---|---|---|
| Number of Participants Who Reported Nausea at 30 Minutes Post Treatment | 13 | 11 |
Geometric Mean Salivary Cortisol level.
| nmol/L | Naloxone | Placebo |
|---|---|---|
| Cortisol | 3.22 ± 2.18 | 3.37 ± 1.96 |
Geometric Mean Salivary Cortisol level.
| nmol/L | Naloxone | Placebo |
|---|---|---|
| Cortisol | 3.61 ± 2.26 | 2.90 ± 2.19 |
Summed score of Subjective Opiate Withdrawal Scale (SOWS). Scale consists of 16 items answered on a 5 point numeric rating scale. Score range is 0 (lesser withdrawal symptoms) to 64 (greater withdrawal symptoms). Scores were assessed at 10 minutes after Naloxone, and at a separate visit, 10 minutes after Placebo, among participants who completed both study visits.
| score on a scale | Naloxone | Placebo |
|---|---|---|
| Subjective Opiate Withdrawal Scale | 5.67 ± 3.65 | 5.03 ± 3.58 |
Mean score on subset of 5 items (which used a 5 point numeric rating response scale) from the Subjective Opiate Withdrawal Scale (SOWS). This summed score can range from 0 (corresponding to lesser withdrawal symptoms) to 20 (corresponding to greater withdrawal symptoms).
| score on a scale | Naloxone | Placebo |
|---|---|---|
| Subjective Opiate Withdrawal Scale (Abbreviated) | 1.42 ± 1.35 | 1.53 ± 1.50 |
Reward-Driven Eating Scale (RED) total score ranges from 0 (lower reward-driven eating) to 52 (higher reward-driven eating).
| score on a scale | Experimental: Naloxone, Then Placebo | Placebo, Then Naloxone |
|---|---|---|
| Reward-Driven Eating Scale (RED) | 38.1 ± 6.1 | 36.8 ± 5.2 |
Impulsivity, measured by the Delayed Discounting cognitive task, based on a series of 30 computer-administered trials or questions. Indifference points (a measure of how much a person values a delayed reward) are determined for time delays of: 1 day, 7 days, 30 days, 180 days, and 365 days, and these are used to calculate an Area Under the Curve which ranges from 0 to 1 (lower numbers indicate higher impulsivity) as a metric of probability.
| Probability | Experimental: Naloxone, Then Placebo | Placebo, Then Naloxone |
|---|---|---|
| Impulsivity (Delayed Discounting) | 0.69 ± 0.21 | 0.57 ± 0.29 |
Collected over Two days (each study intervention visit was conducted over approximately 4 hours, with the 2 interventions administered on a total of 2 separate visit days).. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Naloxone, Then Placebo | 0/23 (0%) | 0/23 (0%) | 0/23 (0%) |
| Placebo, Then Naloxone | 0/18 (0%) | 0/18 (0%) | 0/18 (0%) |
| Age, Categorical(Participants) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 23 | 18 | 41 |
| >=65 years | 0 | 0 | 0 |
| Age, Continuous(years) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| Mean | 30.5 ± 6.5 | 33.1 ± 6.5 | 31.6 ± 6.5 |
| Sex: Female, Male(Participants) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| Female | 23 | 18 | 41 |
| Male | 0 | 0 | 0 |
| Ethnicity (NIH/OMB)(Participants) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| Hispanic or Latino | 0 | 3 | 3 |
| Not Hispanic or Latino | 23 | 15 | 38 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race/Ethnicity, Customized(Participants) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| Black or African American | 0 | 2 | 2 |
| Asian or Pacific Islander | 3 | 0 | 3 |
| White | 16 | 15 | 31 |
| More than one race | 4 | 1 | 5 |
| Region of Enrollment(Participants) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| United States | 23 | 18 | 41 |
| Weight, kg(kilograms) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| Mean | 104.3 ± 23.9 | 99.5 ± 17.0 | 102.2 ± 21.1 |
| Body Mass Index (BMI)(kg/m^2) | Naloxone, Then Placebo | Placebo, Then Naloxone | Total |
|---|---|---|---|
| Mean | 38.1 ± 7.1 | 36.4 ± 4.2 | 37.3 ± 6.0 |
2 further baseline measures are reported on the registry.
Documents are hosted by the registry — open the source record to download them.
Plan to share: No
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University of California, San Francisco