IntroductionDepression symptoms in bipolar disorder have debilitating effects on functioning and quality of life (QoL).ObjectivesTo assess effects of 8 weeks of quetiapine monotherapy on functioning and QoL in patients with bipolar depression (BPD).AimsTo evaluate functioning and QoL using patient-reported outcomes.MethodsData from 4 trials (BOLDER I and II; EMBOLDEN I and II) of quetiapine (300 and 600 mg/day) in BPD were combined (n = 2593). The Sheehan Disability Scale (SDS) measured functioning (BOLDER II; EMBOLDEN I and II) and the QoL Enjoyment and Satisfaction Questionnaire (Q-LES-Q)-Short Form measured QoL (BOLDER I and II; EMBOLDEN II).ResultsQuetiapine improved overall functioning (mean change [SE] in SDS total score: -7.23 [0.49], -7.49 [0.49], with quetiapine 300 mg/day and quetiapine 600 mg/day, respectively vs placebo (-5.91 [0.54]); P < 0.01 for both). Both doses improved functioning in SDS domains of work/school, social life, and family life/home responsibilities vs placebo (P < 0.05). Quetiapine 600 mg/day reduced days missed from work/school and productivity losses vs placebo (P < 0.01). QoL was improved with both quetiapine doses vs placebo (P < 0.001; least squares mean changes (SE) in Q-LES-Q total score from baseline to Day 57: 9.69 (0.51), 9.95 (0.50), and 6.81 (0.54) with quetiapine 300 mg/day, quetiapine 600 mg/day, and placebo, respectively). Tolerability was consistent with the known safety profile of quetiapine.ConclusionsQuetiapine treatment (300 and 600 mg/day) for 8 weeks significantly improved functioning and QoL vs placebo in patients with BPD.Supported by funding from AstraZeneca Pharmaceuticals LP.