Conners' Adult ADHD Rating Scale-Investigator Rated:Screening Version (CAARS-Inv:SV); 30-item scale (3 subscales): inattention, hyperactivity/impulsivity (9 items each), ADHD Index (12 items). Each item is scored 0 (not at all/never) to 3 (very much/very frequently). Total ADHD symptoms score (SS)=inattention+hyperactivity/impulsivity (range:0-54). Higher score=more impairment. Clinical Global Impressions-ADHD-Severity (CGI-ADHD-S) measures participant's overall severity of ADHD symptoms and scores range from 1 (normal, not at all ill) to 7 (among the most extremely ill participants). Maintenance of response during the randomized withdrawal phase was a reduction of ≥30% in the baseline CAARS-Inv:SV Total ADHD SS and a CGI-ADHD-S score ≤3. Participants had to continuously meet the response criteria, except for 1 excursion after assessment at Week 24 through Week 37 and 1 other excursion after assessment at Week 37 through Week 49. Excursions were not permitted at 2 consecutive visits.

Primary outcome measure analysis was conducted using all randomized participants in the Double-Blind Maintenance/Randomized Withdrawal Period (Study Period 3B).

Relapse was defined as 2 consecutive visits with a CGI-ADHD-S score ≥4 points and a return to ≥80% of participant's baseline (Visit 2) CAARS-Inv:SV Total ADHD Symptom Score (SS). If the participant showed evidence of a return of symptoms at a single visit that met severity criteria described above, and because of worsening symptoms, was unwilling to remain in the study or did not return for a second visit, the participant was also considered to have relapsed.

CAARS-Inv:SV is a 30-item scale (3 subscales): Inattention, Hyperactivity/Impulsivity (9 items each), ADHD Index (12 items). Each item is scored 0 (0=not at all/never) to 3 (very much/very frequently). Total ADHD SS=inattention+hyperactivity/impulsivity (range: 0-54). Higher score=more impairment. CGI-ADHD-S measures participant's overall severity of ADHD symptoms and scores range from 1 (normal, not at all ill) to 7 (among the most extremely ill participants).

Analyses were conducted using all randomized participants in the Double-Blind Period (Study Period 3B).

The AAQoL is a self-reported, 29-item scale assessing functional impairments in adults with ADHD. Each item is rated on a 5-point Likert scale; range: 1 (Not at all/ Never) to 5 (Extremely/Very Often). 5-domains of scale include: work functioning, family relationships, social functioning, activities of daily living (driving, managing finances), and psychological adaptation (life satisfaction, self-esteem). These scores are transformed to a 0-100 point scale (1=0; 2=25; 3=50; 4=75; 5=100), and then the item scores are summed and divided by item count to generate overall scores. The overall scores have the same total range of scores of 0-100, with higher scores indicating better quality of life. Least Squares (LS) Mean values were adjusted for baseline AAQoL score and Investigator/site.

All randomized participants with a baseline and at least 1 post-baseline AAQoL score were included in the analysis.

The CAARS-O:SV is a 30-item observer (typically a significant other or close friend) completed scale containing 3 subscales: inattention (9 items), hyperactivity/impulsivity (9 items), and ADHD Index (12 items). Each item is scored 0-3 (0=not at all/never; 1=just a little/once in a while; 2=pretty much/often; 3=very much/very frequently). Inattention and hyperactivity subscales range from 0-27; ADHD index subscale range is 0-36 with higher scores indicating more impaired participants. Total ADHD symptoms score=sum of the inattention and hyperactivity/impulsivity subscales, ranging from 0-54, with higher scores indicating more impaired participants. Least Squares (LS) Mean values adjusted for treatment, pooled Investigator, and baseline.

Participants with a non-missing baseline and at least 1 post-baseline CAARS-O:SV result within each group, Last Observation Carried Forward (LOCF) were included in the analysis.

CAARS-S:SV is a 30-item participant completed scale containing 3 subscales: inattention (9 items), hyperactivity/impulsivity (9 items), ADHD Index (12 items). 0-3 (0=not at all/never; 1=just a little/once in a while; 2=pretty much/often; 3=very much/very frequently). Inattention and hyperactivity subscales range from 0-27; ADHD index subscale range is 0-36 with higher scores indicating more impaired participants. Total ADHD symptoms score=sum of the inattention and hyperactivity/impulsivity subscales; range: 0-54 with higher scores indicating more impaired participants. Least Squares (LS) Mean values adjusted for treatment, pooled Investigator, and baseline.

Participants with a non-missing baseline and at least 1 post-baseline CAARS-S:SV result within each treatment group, Last Observation Carried Forward (LOCF).

The BRIEF-A:Self Report is a 75-item self-reported measure captures adults' views of their own executive functions/self-regulation in their everyday environment. Items include: Inhibit, Shift, Emotional Control, Self Monitor, Initiate, Working Memory, Plan/Organize, Task Monitor, and Organization of Materials. Behavior is rated on a 3-point scale: 1 (behavior is never observed) to 3 (behavior is often observed). GEC Index Score is a subscore of the 75-item BRIEF-A score, reflects overall functioning and was calculated based on 70 items. Total scores range: 70-210. Lower scores = less perceived impairment. Least Squares (LS) Mean values were adjusted for treatment, pooled Investigator, and baseline.

Participants with a non-missing baseline and at least 1 post-baseline BRIEF-A:Self Report result within each group, Last Observation Carried Forward (LOCF) were included in the analysis.

BRIEF-A:Informant is a 75-item third-party observer's view of the participants' executive functions/self-regulation in their everyday environment. Items include: Inhibit, Shift, Emotional Control, Self Monitor, Initiate, Working Memory, Plan/Organize, Task Monitor, and Organization of Materials. Behavior is rated on a 3-point scale: 1 (behavior is never observed) to 3 (behavior is often observed). GEC Index Score is a subscore of the 75-item BRIEF-A score, reflects overall functioning and was calculated based on 70 items. Total scores range: 70-210. Lower scores = less perceived impairment. Least Squares (LS) Mean values were adjusted for treatment, pooled Investigator, and baseline.

Participants with a non-missing baseline and at least 1 post-baseline BRIEF-A:Informant result within each group, Last Observation Carried Forward (LOCF) were included in the analysis.

The EQ-5D is a Self-reported, 5-item scale to assess health utility (mobility, self-care, usual activities, pain and discomfort, and depression/anxiety). Scoring is on a 3-point scale (1=no health problems, 2=some or moderate problems, 3=major health problems). A preference value Index score is calculated using societal preference developed from a general population-based valuation studies. Index score ranges: United Kingdom (UK): -0.59 to 1.0, United States (US): -0.11 to 1.0, where 1 represents best possible health and 0 represents dead, with <0 interpreted as a health state "worse than dead." A Quality of Life Health State Score visual analog scale (VAS) was assessed, scores range from 0 to 100. Higher scores indicate better health state. Least Square (LS) Mean values were adjusted for treatment, pooled Investigator, baseline.

Participants with a non-missing baseline and at least 1 post-baseline EQ-5D Index Score or VAS score within each group, Last Observation Carried Forward (LOCF) were included in the analysis.