Lisdexamfetamine for Adults With Bulimia Nervosa

Subjects will be asked to report TEAEs to the research team and PI.

Subjects will be weighed using a calibrated hospital scale while wearing a hospital gown and no footwear.

Systolic and diastolic blood pressure will be collected by a study investigator at weekly/biweekly visits.

Heart rate will be collected by a study investigator at weekly/biweekly visits.

Adherence will be calculated as the number of pills not returned divided by the number of days since the last visit, multiplied by 100 to yield a percentage. Subjects with an adherence rate between 80% and 120% will be considered adherent to treatment.

Most relevant concerns for patients with BN taking LDX include electrolyte abnormalities (potassium, sodium, chloride) and hypoglycemia

Most relevant concerns for patients with BN taking LDX include prolonged QTc, hypertension, and tachycardia.

A clinician-observed measure designed to assess suicidal ideations and suicidal behaviours since the last visit in clinical trials. The scale consists of 4 sections. Section 1 regards suicidal ideation and consists of 5 "yes" or "no" questions. Section 2 regards the intensity of ideation and asks the patient to describe their most severe ideation. In regard to that ideation, the patient then indicates frequency, duration, controllability, deterrents, and reasons for ideation. Section 3 regards suicidal behaviour, and indicates if there has been an actual attempt, interrupted attempt, aborted attempt, or preparatory acts/behaviour since the last visit. Additionally, there is a section to indicate if there was suicidal behaviour during the assessment or if there was a suicide since the last visit. Section 4 specifies information about actual attempts only (actual lethality/medical damage and potential lethality).

Subjects will record the number of binge eating episodes in a food diary, which will be validated weekly by a clinician using structured questions from the Eating Disorder Examination Interview inquiring about symptom frequency since the previous study visit.

Subjects will record the number of self-induced vomiting episodes in a diary which will be validated weekly by a clinician using structured questions from the Eating Disorder Examination Interview inquiring about symptom frequency since the previous study visit.

Binge eating and purging days are defined as having one or more episodes of binge eating or purging in a day, respectively.

A clinician-administered scale that assesses the severity of 4 areas of eating disorder psychopathology over the past 4 weeks (28 days): Eating Concern, Weight Concern, Dietary Restraint, and Shape Concern. Overall eating disorder severity is also assessed. A higher score indicates increased severity. To obtain a particular subscale score, the ratings for the relevant items are added together and the sum divided by the total number of items forming the subscale (i.e., the mean of all subscale items). To obtain a global score, the four subscales scores are summed and the resulting total divided by the number of subscales (i.e., the mean of all items). The scale consists of 28 items.

This 30-item measure assesses the personality/behavioural construct of impulsiveness and is widely accepted as the primary self-report measure of impulsivity. Items are ranked on a 1-4 scale (1 being "rarely/never" and 4 being "almost always/always"). A total score can be calculated using all 30 items. A higher score indicates higher levels of impulsivity.

A 10-item, clinician-administered rating scale for measuring the severity of OCD symptoms as they relate to binge eating. A higher score indicates increased severity. An obsessional subtotal can be calculated by adding items 1-5. A compulsion subtotal can be calculated by adding items 6-10. A total score can be calculated by adding all items. This version will be further modified to assess both binge eating and purging behaviours.

A 51-item self-report scale that assesses three areas of eating behaviours: Cognitive restraint of eating, disinhibition, and hunger.

A 16-item self-report measure of the severity of psychosocial impairment due to eating disorder features over the past 28 days. Each item is ranked on a 0-3 scale (0 being "not at all" and 3 being "a lot").

Responders defined as ≥50% reduction in the number of binge and/ or purge episodes from baseline to the last two preceding weeks of treatment.

Cessation defined as 100% reduction in binge and/or purge episodes in the last 28 days of treatment.

A 7-point scale that requires the clinician to rate the severity of the patient's illness at time of assessment, relative to the clinician's past experience with patients who have the same diagnosis.

As measured by the Modified Two-Step Task. This task examines exploration/exploitation (choice consistency), as well as goal-directed (i.e., model-based) and habitual (i.e., model-free) control.

A 26-item measure of one's confidence in performing coping behaviors when faced with life challenges.

A 17-item measure of the extent to which subjects perceive responsibility for their behaviour.

A 3-item measure that assesses the perceived value of changing binge eating, confidence in ability to change binge eating, and readiness to change binge eating.

An exploratory interview which aims to collect qualitative information on each patient's experiences with the study medication (i.e., from the patient's perspective, how does the medication affect their eating disorder symptoms?).