Abstract Introduction Insomnia and mood disorders are commonly comorbid. Many patients with partial remission of depression have insomnia symptoms remaining. In a recent study of lemborexant (LEM), a dual orexin-receptor antagonist approved for the treatment of insomnia, open-label LEM significantly improved symptoms of both insomnia and depression in a comorbid patient population. We report the symptoms on the Hamilton Depression Rating Scale (HAM-D-17) impacted by LEM. Methods This multicenter, prospective intervention study enrolled participants with insomnia disorder diagnosed with major depressive disorder (MDD) or bipolar disorder (BD) receiving stable antidepressant treatment. MDD add-on (n=29) and BD add-on (n=15) cohorts included participants with prior insomnia medication; MDD mono (n=23) and BD mono (n=15) cohorts included participants without concomitant hypnotic medication. LEM starting dose was 5 mg and could be titrated up/down. Mood disorder severity was measured with HAM-D-17 at baseline (BL) and Weeks 4/8/12. HAM-D-17 assesses severity of depression over the past week; higher scores indicate more severe depression, and 3 items (rating scale 0–2) evaluate insomnia symptoms (items 4–6; early, middle, and late insomnia, respectively). This analysis considered each item to determine those affected by LEM treatment. Results As previously reported, total HAM-D-17 scores for the 4 cohorts decreased significantly (improved) compared with BL at 4 weeks; these improvements were maintained over 12 weeks. This was also true when the 3 items associated with insomnia were excluded. At Week 12, significant decreases (improvements) in scores for HAM-D-17 items 1–8, 10, 11, and 13–15 were observed. However, the item scores most impacted by LEM treatment were the 3 insomnia items, as well as the overall depression item (rated on a scale from 0–4). The magnitude of change from BL was at least 0.4 points in the total patient population (early insomnia: BL 1.21, Week 4 −0.71; middle insomnia: BL 1.21, Week 4 −0.50; late insomnia: BL 0.91, Week 4 −0.53; depression: BL 1.56, Week 4 −0.44). Conclusion The majority of change (improvement) on the HAM-D-17 with LEM treatment was related to changes in sleep symptoms in this comorbid patient population. Support (if any) Eisai Inc.
Takaesu et al. (Fri,) studied this question.