Naltrexone plus bupropion combination medication maintenance treatment for binge-eating disorder following successful acute treatments: randomized double-blind placebo-controlled trial

Reward and Inhibitory Control as Mechanisms and Treatment Targets for Binge Eating Disorder

PURPOSE OF REVIEW

Recent research has highlighted alterations in reward and inhibitory control among individuals with binge eating disorder, identifying both constructs as potential targets for treatment. Treatments targeting reward and inhibitory control for binge eating disorder are emerging. This review aims to summarize the recent literature evaluating reward and inhibitory control in binge eating disorder compared to weight-matched controls using behavioral paradigms and neuroimaging. This review also aims to summarize recent literature evaluating treatments for binge eating targeting these mechanisms and highlights additional work needed in these areas.

RECENT FINDINGS

Reward hypersensitivity and impaired inhibitory control are mechanisms underlying binge eating disorder. Individuals with binge eating disorder experience higher initial reward to food, and later, higher anticipatory reward but lower experienced food reward which maintains binge eating behavior. Treatments targeting reward and inhibitory control for binge eating include behavioral, computerized trainings, pharmacological, and neuromodulation treatments. The majority of trials are small but demonstrate promise in reducing binge eating and targeting theorized mechanisms. Larger, randomized trials are needed. Changes in reward and inhibitory control are present in individuals with binge eating disorder and treatments targeting these mechanisms demonstrate initial promise. Greater research is needed evaluating reward and inhibitory control simultaneously and with weight-matched comparison groups, as well as larger randomized trials that target both processes simultaneously.

Lisdexamfetamine maintenance treatment for binge-eating disorder following successful treatments: randomized double-blind placebo-controlled trial

BACKGROUND

Controlled research examining maintenance treatments for responders to acute interventions for binge-eating disorder (BED) is limited. This study tested efficacy of lisdexamfetamine (LDX) maintenance treatment amongst acute responders.

METHODS

This prospective randomized double-blind placebo-controlled single-site trial, conducted March 2019 to September 2023, tested LDX as maintenance treatment for responders to acute treatments with LDX-alone or with cognitive-behavioral therapy (CBT + LDX) for BED with obesity. Sixty-one (83.6% women, mean age 44.3, mean BMI 36.1 kg/m2) acute responders were randomized to LDX (N = 32) or placebo (N = 29) for 12 weeks; 95.1% completed posttreatment assessments. Mixed-models and generalized-estimating equations comparing maintenance LDX v. placebo included main/interactive effects of acute (LDX or CBT + LDX) treatments to examine their predictive/moderating effects.

RESULTS

Relapse rates (to diagnosis-level binge-eating frequency) following maintenance treatments were 10.0% (N = 3/30) for LDX and 17.9% (N = 5/28) for placebo; intention-to-treat binge-eating remission rates were 59.4% (N = 19/32) and 65.5% (N = 19/29), respectively. Maintenance LDX and placebo did not differ significantly in binge-eating but differed in weight-loss and eating-disorder psychopathology. Maintenance LDX was associated with significant weight-loss (-2.3%) whereas placebo had significant weight-gain (+2.2%); LDX and placebo differed significantly in weight-change throughout treatment and at posttreatment. Eating-disorder psychopathology remained unchanged with LDX but increased significantly with placebo. Acute treatments did not significantly predict/moderate maintenance-treatment outcomes.

CONCLUSIONS

Adults with BED/obesity who respond to acute lisdexamfetamine treatment (regardless of additionally receiving CBT) had good maintenance during subsequent 12-weeks. Maintenance lisdexamfetamine, relative to placebo, did not provide further benefit for binge-eating but was associated with significantly better eating-disorder psychopathology outcomes and greater weight-loss.

Endogenous opiates and behavior: 2023

This paper is the forty-sixth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2023 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug and alcohol abuse (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Treatment of Eating Disorders: Current Status, Challenges, and Future Directions

Specific psychological treatments have demonstrated efficacy and represent the first-line approaches recommended for anorexia nervosa, bulimia nervosa, and binge-eating disorder. Unfortunately, many patients, particularly those with anorexia nervosa, do not derive sufficient benefit from existing treatments, and better or alternative treatments for eating disorders are needed. Less progress has been made in developing pharmacologic options for eating disorders. No medications approved for anorexia nervosa exist, and only one each exists for bulimia nervosa and for binge-eating disorder; available data indicate that most patients fail to benefit from available medications. Longer and combined treatments have generally not enhanced outcomes. This review presents emerging findings from more complex and clinically relevant adaptive treatment designs, as they offer some clinical guidance and may serve as models for future enhanced treatment research.

Food Cravings and Obesity in Women with Polycystic Ovary Syndrome: Pathophysiological and Therapeutic Considerations

Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, constitutes a metabolic disorder frequently associated with obesity and insulin resistance (IR). Furthermore, women with PCOS often suffer from excessive anxiety and depression, elicited by low self-esteem due to obesity, acne, and hirsutism. These mood disorders are commonly associated with food cravings and binge eating. Hypothalamic signaling regulates appetite and satiety, deteriorating excessive food consumption. However, the hypothalamic function is incapable of compensating for surplus food in women with PCOS, leading to the aggravation of obesity and a vicious circle. Hyperandrogenism, IR, the reduced secretion of cholecystokinin postprandially, and leptin resistance defined by leptin receptors' knockout in the hypothalamus have been implicated in the pathogenesis of hypothalamic dysfunction and appetite dysregulation. Diet modifications, exercise, and psychological and medical interventions have been applied to alleviate food disorders, interrupting the vicious circle. Cognitive-behavioral intervention seems to be the mainstay of treatment, while the role of medical agents, such as GLP-1 analogs and naltrexone/bupropion, has emerged.

Psychotropic Drug-Related Weight Gain and Its Treatment

Psychotropic drug-related weight gain (PDWG) is a common occurrence and is highly associated with non-initiation, discontinuation, and dissatisfaction with psychiatric drugs. Moreover, PDWG intersects with the elevated risk for obesity and associated morbidity that has been amply reported in the psychiatric population. Evidence indicates that differential liability for PDWG exists for antipsychotics, antidepressants, and anticonvulsants. During the past two decades, agents within these classes have become available with significantly lower or no liability for PDWG and as such should be prioritized. Although lithium is associated with weight gain, the overall extent of weight gain is significantly lower than previously estimated. The benefit of lifestyle and behavioral modification for obesity and/or PDWG in psychiatric populations is established, with effectiveness similar to that in the general population. Metformin is the most studied pharmacological treatment in the prevention and treatment of PDWG, and promising data are emerging for glucagon-like peptide-1 (GLP-1) receptor agonists (e.g., liraglutide, exenatide, semaglutide). Most pharmacologic antidotes for PDWG are supported with low-confidence data (e.g., topiramate, histamine-2 receptor antagonists). Future vistas for pharmacologic treatment for PDWG include large, adequately controlled studies with GLP-1 receptor agonists and possibly GLP-1/glucose-dependent insulinotropic polypeptide co-agonists (e.g., tirzepatide) as well as specific dietary modifications.

Naltrexone/bupropion for binge-eating disorder: A randomized, double-blind, placebo-controlled trial

OBJECTIVE

Binge-eating disorder (BED) is a prevalent psychiatric disorder associated with obesity. Few evidence-based treatments exist for BED, particularly pharmacological options. This study tested the efficacy of naltrexone/bupropion for BED.

METHODS

A randomized, double-blind, placebo-controlled, 12-week trial tested naltrexone/bupropion for BED with and without obesity. Eighty-nine patients (70.8% women, 69.7% White, mean age 45.7 y, mean BMI 35.1 kg/m2 , 77.5% with BMI ≥ 30 kg/m2 ) were randomized to placebo (n = 46) or naltrexone/bupropion (n = 43), with randomization stratified by obesity status and gender; 92.1% completed post-treatment assessments.

RESULTS

Mixed models of binge-eating frequency revealed significant reductions that did not differ significantly between naltrexone/bupropion and placebo. Logistic regression of binge-eating remission rates revealed that naltrexone/bupropion and placebo did not differ significantly. Obesity status did not predict, or moderate, binge-eating outcomes considered either continuously or categorically. Mixed models revealed that naltrexone/bupropion was associated with significantly greater percentage weight loss than placebo. Logistic regression revealed that naltrexone/bupropion had significantly higher rates of attaining ≥5% weight loss than placebo (27.9% vs. 6.5%). Obesity status did not predict or moderate weight-loss outcomes.

CONCLUSIONS

Naltrexone/bupropion did not demonstrate effectiveness for reducing binge eating relative to placebo but showed effectiveness for weight reduction in patients with BED. Obesity status did not predict or moderate medication outcomes.