In the United States, an estimated 30 million individuals have an eating disorder.¹ Associated with the highest mortality rate of all mental illnesses, eating disorders claim the lives of nearly 20% of those affected.¹

Binge-eating disorder is a serious eating disorder that is characterized by a frequent consumption of unusually large amounts of food within a short, 2-hour period and the uncontrollable urge to continue eating during an episode.² Approximately 1% to 5% of the US population is affected by binge-eating disorder; 60% of those affected are women, and 40% are men.³

Individuals with binge-eating disorder often eat when they are full or not hungry, eat rapidly during a binge episode, eat until uncomfortably full, or eat alone or in secret. Although the majority of individuals with binge eating disorder are overweight or obese, some individuals with the dis­order may be of normal weight.² A binge-eating episode is often followed by feelings of shame, disgust, guilt, or upsetness.²

Binge-eating disorder can have a profound impact on affected individuals. It can lead to obesity and obesity-related medical conditions, including joint problems, heart disease, type 2 diabetes, gastroesophageal reflux disease, and several sleep-related breathing disorders.² Other complications associated with binge eating disorder include gallbladder disease, high blood pressure, high cholesterol levels, low self-esteem, social isolation, poor quality of life, and problems functioning at work or in social settings.^2,3 Binge-eating disorder is also associated with depression, bipolar disorder, anxiety, and substance abuse disorders.²

Despite the serious health implications associated with eating disorders and the fact that the majority of these disorders can be effectively treated, only 1 in 10 individuals receives treatment.¹ Treatment for eating disorders typically requires psychotherapy (eg, cognitive behavioral therapy, interpersonal psychotherapy, or dialectical behavior therapy) and medication.²

Binge-eating disorder should be treated before initiating weight-loss programs, because dieting can trigger binge eating episodes that interfere with weight loss.² Although antidepressants and anticonvulsants are sometimes used to help reduce the symptoms of binge eating, until recently, there were no US Food and Drug Administration (FDA)-approved phar­macologic options available to treat binge eating disorder.^2,4

The First Treatment Option for Adults with Binge-Eating Disorder

On January 30, 2015, lisdexamfetamine dimesylate (Vyvanse; Shire), an oral central nervous system (CNS) stimulant, became the first medication to be approved by the FDA for the treatment of adults with binge-eating disorder.⁴ This approval marks the expanded use of lisdexamfetamine dimesylate, which was previously approved by the FDA in 2007 (also under the name Vyvanse; Shire) for the treatment of patients aged >6 years with attention-deficit/hyperactivity disorder.⁴ Lisdexamfeta­mine dimesylate is not indicated for weight loss. The safety and effectiveness of lisdexamfetamine dimesylate for the treatment of obesity have not been established.^4,5

Mitchell Mathis, MD, Director of the Division of Psychiatry Products in the FDA’s Center for Drug Evaluation and Research, said, “Binge eating can cause serious health problems and difficulties with work, home, and social life. The approval of Vyvanse provides physicians and patients with an effective option to help curb episodes of binge eating.⁴

The FDA granted lisdexamfetamine dimesylate a priority review based on its intended use to treat a serious disease or condition and its potential to provide a significant improvement over available therapies. As part of its approval, lisdexamfetamine dimesylate must be dispensed with a medication guide that informs patients about the drug’s appropriate use and potential risks.⁴

Dosing and Administration

The recommended starting dose of lisdexamfetamine dimesylate is 30 mg daily, which should be titrated in increments of 20 mg weekly to achieve the recommended target dose of 50 mg to 70 mg daily (Table 1). Patients should be assessed for the presence of cardiac disease before starting treatment with lisdexamfetamine dimesylate.⁵

Lisdexamfetamine dimesylate is available as a capsule in several dosage strengths, including 10 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, and 70 mg.⁵

Mechanism of Action

Lisdexamfetamine dimesylate, a CNS stimulant, is a prodrug of dextroamphetamine. Amphetamines are non-catecholamine sympathomimetic amines with CNS stimulant activity. Amphetamines block the reuptake of norepinephrine and dopamine into the presynaptic neuron and increase the release of these monoamines into the extraneuronal space. The parent drug, lisdexamfetamine dimesylate, does not bind to the sites responsible for the reuptake of norepinephrine and dopamine in vitro.⁵

Clinical Trials Efficacy: Study 10 and Study 11

The efficacy of lisdexamfetamine dimesylate for the treatment of adults with binge eating disorder was demonstrated in 2 randomized, double-blind, placebo-controlled, phase 3 clinical trials, Study 10 and Study 11.^5,6 Study 10 included 374 patients and Study 11 included 350 patients aged 18 to 55 years with moderate­to-severe binge-eating disorder.^5,6

The diagnosis of binge-eating disorder was confirmed using the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for binge-eating disorder.⁵ The severity of binge-eating disorder was determined based on having at least 3 binge days weekly for 2 weeks before the baseline visit as well as a Clinical Global Impression severity score of ≥4 at the baseline visit. A “binge day” was defined as a day with at least 1 binge eating episode, as determined based on the patient’s daily binging diary^.6

In both studies, the primary efficacy outcome was defined as the change from baseline in the number of binge days weekly at week 12. The baseline was defined as the weekly average of the number of binge days weekly for the 14 days before the baseline visit.⁶

In Study 10 and Study 11, patients who received lisdexamfetamine dimes­y­late at doses of 50 mg daily or 70 mg daily had a significantly greater reduction from baseline in the mean number of weekly binge days at week 12 compared with placebo (Study 10, –3.87 vs –2.51, respectively; Study 11, –3.92 vs –2.26, respectively). Table 2 lists the primary efficacy results.

Furthermore, patients who received lisdexamfetamine dimesylate showed greater improvements across key secondary outcomes compared with patients who received placebo, with a higher proportion of patients who improved on the Clinical Global Impression improvement scale, a higher proportion of patients with 4-week binge cessation, and a greater reduction in the Yale-Brown Obsessive Compulsive Scale modified for the binge-eating total score.⁶

Safety

The most common adverse reactions (incidence rate ≥5% and at least twice the rate of placebo) associated with the use of lisdexamfetamine dimesylate in adults with binge-eating disorder were dry mouth (36%), insomnia (20%), decreased appetite (8%), increased heart rate (7%), constipation (6%), feeling jittery (6%), and anxiety (5%).⁶

In controlled studies of patients aged 18 to 55 years, 5.1% (19/373) of patients who received lisdexamfetamine dimes­y­late discontinued treatment as a result of adverse reactions compared with 2.4% (9/372) of patients who received placebo. No single adverse reaction led to treatment discontinuation in ≥1% of patients who received lisdexamfetamine dimesylate.⁶

Drug Interactions: Acidifying and Alkalinizing Agents

Agents that alter urinary pH levels can also alter blood levels of amphetamine. Acidifying agents decrease amphetamine blood levels, and alkalinizing agents increase amphetamine blood levels. The dose of lisdexamfetamine dimesylate should be adjusted accordingly when used together with acidifying or alkalinizing agents.⁶

Contraindications

Lisdexamfetamine dimesylate is contraindicated in patients with a known hypersensitivity to amphetamine agents or other ingredients in lisdexamfetamine dimesylate. The use of lisdexamfetamine dimesylate is contraindicated with monoamine oxidase (MAO) inhibitors, or within 14 days of the last MAO inhibitor dose.⁶

Warnings and Precautions

Boxed warning. The prescribing information for lisdexamfetamine dimesylate contains a boxed warning stating that CNS stimulants, including lisdexamfetamine dimesylate, have a high risk for abuse and dependence. Patients should be evaluated for the risk of abuse before prescribing lisdexamfetamine dimesylate, and be monitored for signs of abuse and dependence during therapy with lisdexamfetamine dimesylate.⁶

Serious cardiovascular reactions. Sudden death in children and adolescents with serious heart problems, as well as sudden death, stroke, and myocardial infarction in adults have been reported with the use of lisdexamfetamine dimesylate. This medication should not be used in patients with known structural cardiac abnormalities, cardiomyopathy, serious heart arrhythmia, or coronary artery disease.⁶
Blood pressure and heart rate increases. CNS stimulants cause an increase in blood pressure. All patients should be monitored for hypertension and tachycardia during therapy with lisdexamfetamine dimesylate.⁶

Psychiatric adverse reactions. Lisdexamfetamine dimesylate may cause psychotic or manic symptoms in patients with no history of psychosis, or an exacerbation of symptoms in patients with preexisting psychosis. Patients should be evaluated for bipolar disorder before taking stimulants.⁶

Peripheral vasculopathy. Stimulants are associated with peripheral vasculopathy, including Raynaud’s phenomenon. Careful observation for digital changes is necessary during treatment with stimulants.⁵

Use in Specific Populations

Pregnancy. Based on animal data, lisdexamfetamine dimesylate may cause fetal harm and should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus.⁶

Nursing. Amphetamines are excreted into human milk. Because of the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue lisdexamfetamine dimesylate, taking into account the importance of the drug to the mother.⁶

Pediatric use. The safety and effectiveness of lisdexamfetamine dimes­ylate in individuals with binge eating disorders aged <18 years have not been established.⁶

Geriatric use. Clinical studies of lisdexamfetamine dimesylate did not include sufficient numbers of patients aged ≥65 years to determine whether they respond differently from younger patients.⁶

Renal impairment. Because of reduced clearance in patients with severe renal impairment, the maximum dose of lisdexamfetamine dimesylate should not exceed 50 mg daily. The maximum recommended dose of lisdexamfetamine dimesy­late in patients with end-stage renal disease is 30 mg daily.⁶

Gender. No dosage adjustment of lisdexamfetamine dimesylate is necessary on the basis of gender.⁶

Conclusion

Lisdexamfetamine dimesylate, a CNS stimulant, is the first FDA-approved therapeutic option for adults with binge eating disorder. nLisdexamfetamine dimesylate modulates the dopaminergic and noradrenergic systems, helping to control episodes of binge eating, which are associated with significant weight gain and other serious health complications.

In 2 identically designed phase 3 clinical trials that included 724 adults, treatment with lisdexamfetamine dimesylate was significantly superior to placebo at decreasing binge eating days weekly compared with baseline in adults with moderate-to-severe binge eating disorder. Therapy with lisdexam fetamine dimesylate also demonstrated a greater improvement in key secondary end points, including the Clinical Global Impression improvement scale, compared with placebo.⁷

References
1. Eating Disorders Coalition. Facts about eating disorders: what the research shows. www.eatingdisorderscoalition.org/documents/FactsAboutEatingDisorders 2014.pdf. Accessed May 9, 2015.
2. Mayo Clinic staff. Diseases and ­conditions: binge-eating disorder. April 9, 2015. www.mayoclinic.org/diseases-conditions/binge-eating-disorder/­basics/definition/ con-20033155?p=1. Accessed May 9, 2015.
3. National Eating Disorders Associ­ation. Binge eating disorder. www.national eatingdisorders.org/binge-eating-disorder. Accessed May 13, 2015.
4. US Food and Drug Administration. FDA expands uses of Vyvanse to treat binge-eating disorder. Press release. January 30, 2015. www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm432543.htm. Accessed May 5, 2015.
5. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed. Arlington, VA: American Psychiatric Publishing; 2000.
6. Vyvanse (lisdexamfetamine dimes­ylate) capsules [prescribing information]. Wayne, PA: Shire US Inc; April 2015.
7. McElroy S, Ferreira-Cornwell MC, Gasior M, et al. Randomized controlled safety and efficacy trials of lisdexamfetamine dimesylate for adults with moderate to severe binge eating disorder. Presented at: American Psychiatric Association 167th Annual Meeting; May 3-7, 2014; New York, NY.