0458 The Sleep Diary Questionnaire: An Analysis of Meaningful Change in Subjective Total Sleep Time Using Phase 2 and Phase 3 Clinical Trial Data

Abstract

Abstract Introduction The Sleep Diary Questionnaire (SDQ) is a new content-valid 17-item sleep diary adapted from the Consensus Sleep Diary. It assesses key sleep parameters including total time asleep the previous night or “subjective total sleep time” (sTST). People with insomnia value increasing sTST as a key treatment outcome. We estimated meaningful withinpatient change for sTST from two clinical trials in adults with insomnia. Methods Data from a 2-week, phase 2 open-label trial of zolpidem (NCT03056053) and blinded data from a 3-month, phase 3 randomized placebo-controlled trial of daridorexant (NCT03545191) were used. In both trials, subjects completed the SDQ daily before and during treatment. Changes in weekly average sTST were calculated using anchor-based analyses that included patient and clinicianreported outcome measures whose correlations with change in weekly average sTST were at least moderate (Spearman correlation coefficient ≥|0.3|). The outcome measures were Insomnia Severity Index, Patient Global Assessment of Disease Severity, Patient Global Impression of Severity, Patient Global Impression of Change, Clinician Global Impression of Severity, and Clinician Global Impression of Change. Distribution-based analyses calculated standard error of measurement (SEM) as supportive evidence. Change estimates from the anchor and distributionbased analyses were “triangulated” to identify a value where they converged. Results In the phase 2 trial (N=114), mean increases in sTST from baseline in subjects with meaningful improvements on the anchors were 60.1–83.2 min at day 8 and 55.5–93.5 min at day 15. SEM was 51.1 min at day 8 and 55.5 min at day 15. In the phase 3 trial (N=930, pooled across treatment arms), mean increases in sTST were 36.5–76.2 min at month 1 and 47.3–87.7 min at month 3. SEM was 43.2 min at month 1 and 53.3 min at month 3. Triangulation of these results supported a meaningful change threshold of 55 min. Conclusion Our findings support the importance of using sTST to assess insomnia from the patient’s perspective and provide useful information that an increase in sleep time of almost 1 hour is meaningful to patients. Support (If Any) This work was funded by Idorsia Pharmaceuticals Ltd.