JNJ-42847922's Antidepressant Mechanism Explored in MDD Participants Based on Hyper-Arousal Status

Major Depressive Disorder (MDD) is a debilitating psychiatric condition marked by a spectrum of symptoms including affective, cognitive, and somatic disturbances. A significant yet often under-addressed aspect of MDD pathology involves profound disruptions in sleep-wake cycles and heightened arousal. Current standard-of-care treatments often fall short in effectively managing these specific symptoms, leading to residual impairment and reduced quality of life. The orexin system, a hypothalamic neuropeptide pathway, is a key regulator of arousal, wakefulness, and sleep-wake stability. Modulating this system, particularly the orexin-2 receptor, presents a promising therapeutic avenue for addressing the hyper-arousal and sleep disturbances frequently observed in MDD, potentially offering a more targeted antidepressant mechanism.

This exploratory, randomized, placebo-controlled clinical trial was designed to investigate the antidepressant mechanism of JNJ-42847922 in participants diagnosed with Major Depressive Disorder. The study aimed to determine if the magnitude of treatment effect on depressive symptoms differed across varying levels of hyper-arousal status. Participants were randomized to receive either JNJ-42847922 or placebo. Primary outcome measures included clinician-rated depression scores using the Hamilton Rating Scale for Depression-17 (HDRS17), its sleep item-adjusted variant, an anxiety/somatization factor score, and the HAM-D6 subscale. Hyper-arousal status was characterized using objective and subjective measures such as sleep parameters, the Ruminative Response Scale (RRS), Sleep and Worry Visual Analogue Scales (VAS), quantitative electro-encephalography (qEEG), and heart rate variability (HRV). Functional Magnetic Resonance Imaging (fMRI) and Transcranial Magnetic Stimulation-Electroencephalography (TMS-EEG) were also employed to assess cortical reactivity.