Biology and Experience of Eating in Women With Obesity

Phase 2

Completed

Brief Summary: The purpose of this study is to understand how the opioid system is involved in eating behavior.

Detailed Description: 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.

Recruitment & Eligibility

Inclusion Criteria

Obese, as defined by BMI greater than or equal to 30
Self-reported binge eating as defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), in the last 4 weeks
If sexually active with men, must agree to use birth control until the final study visit is complete (e.g., barrier methods, oral contraceptive)
Subject must be able to complete written informed consent procedures and be able to comply with the requirements of the study.

Exclusion Criteria

Pregnant or breastfeeding
Severe hypotension (< 90/60 mmHg)
Recent or current use of vasoconstrictor or vasodilator medication
Current or history of diabetes
Allergies to any ingredients in naloxone hydrochloride
History of or current alcoholism or drug dependence
Bulimia Nervosa as defined in DSM 5
Current or past use of opiate-containing medications in the last 30 days
Plan to use opiate-containing medications during study participation period
Medical conditions that are contraindicated with intranasal procedures: Nasal septal abnormalities, nasal trauma, epistaxis, excessive nasal mucus, and intranasal damage caused by the use of substances (e.g., cocaine)
Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the subject or the quality of the data

Arm && Interventions

Group	Intervention	Description
Naloxone, then Placebo	Placebo	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)
Placebo, then Naloxone	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)
Naloxone, then Placebo	Naloxone	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)
Placebo, then Naloxone	Naloxone	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)

Primary Outcome Measures

Name	Time	Method
Number of Participants Who Reported Nausea at 10 Minutes Post Treatment	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.
Number of Participants Who Reported Nausea at 30 Minutes Post Treatment	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.

Secondary Outcome Measures

Name	Time	Method
Cortisol	55 minutes post-treatment	Geometric Mean Salivary Cortisol level.
Subjective Opiate Withdrawal Scale	10 minutes post-treatment	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.
Subjective Opiate Withdrawal Scale (Abbreviated)	30 minutes post-treatment	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).