Insomnia disorder may affect mental health, increasing suicidal risk. Targeting insomnia is crucial in the clinical practice. Sixty-six consecutive patients with insomnia disorder according with the DSM-5-TR criteria were treated with the dual orexin receptor antagonist, daridorexant 50 mg. Baseline (T0), 1 month (T1) and 3 month (T2) evaluations were performed. Insomnia severity (Insomnia Severity Index), mood, anxiety symptoms and suicidal risk (Beck Depression Inventory-II, Young Mania Rating Scale, Self-Reported Anxiety Scale, Suicidal Ideation Scale), dysfunctional insomnia-cognitive factors and pre-sleep arousal (Dysfunctional Beliefs About Sleep, Pre-Sleep Arousal Scale) were evaluated. The final sample included 66 patients (n = 36, 54% females, mean age 60 ± 13.6 years). Most of them, 64%, suffered from insomnia disorder comorbid with unipolar/bipolar depression, anxiety disorders and substance use disorders. Repeated ANOVA analyses showed that Insomnia Severity Index, Dysfunctional Beliefs About Sleep and Pre-Sleep Arousal Scale total score decreased across time (F = 68.818, p < 0.001; F = 47.561, p < 0.001; F = 28.142, p < 0.001, respectively). Similarly, Beck Depression Inventory-II, Self-Reported Anxiety Scale, Young Mania Rating Scale, and Suicidal Ideation Scale significantly decreased over time (p < 0.001). Predictors of insomnia remission (Insomnia Severity Index < 8) at T1 were improvement of Insomnia Severity Index at T1 (F = 60.205, p < 0.001), and improvement of Dysfunctional Beliefs About Sleep at T1 (F = 4.432, p = 0.041). Insomnia remission at T2 was best predicted by improvement of Dysfunctional Beliefs About Sleep at T2 (F = 3.993, p = 0.023). Multiple-regression models showed that clinical improvement of Beck Depression Inventory-II was best predicted by improvement in Dysfunctional Beliefs About Sleep at T1 and T2, manic symptoms by Insomnia Severity Index at T2, anxiety symptoms by Dysfunctional Beliefs About Sleep, Insomnia Severity Index and somatic Pre-Sleep Arousal Scale at T1 and T2. With the caution of a naturalistic design, early experience with daridorexant showed that by targeting insomnia it may be possible to improve not only insomnia symptoms but also comorbid symptoms.© 2024 European Sleep Research Society.