Daridorexant

Daridorexant, formerly known as nemorexant, is a selective dual orexin receptor antagonist used to treat insomnia. Insomnia is characterized by difficulties with sleep onset and/or sleep maintenance and impairment of daytime functioning. It chronically affects the person's daily functioning and long-term health effects, as insomnia is often associated with comorbidities such as hypertension, diabetes, and depression. Conventional treatments for insomnia include drugs targeting gamma-aminobutyric acid type-A (GABA-A), serotonin, histamine, or melatonin receptors; however, undesirable side effects are frequently reported, such as next-morning residual sleepiness, motor incoordination, falls, memory and cognitive impairment. Novel drugs that target orexin receptors gained increasing attention after discovering the role of orexin signalling pathway in wakefulness and almorexant, an orexin receptor antagonist that improved sleep. Daridorexant was designed via an intensive drug discovery program to improve the potency and maximize the duration of action while minimizing next-morning residual activity.

Daridorexant works on orexin receptors OX1R and OX2R to block the binding of orexins, which are wake-promoting neuropeptides and endogenous ligands to these receptors. Daridorexant reduces overactive wakefulness: in the investigational trials, daridorexant reportedly improved sleep and daytime functioning in patients with insomnia. It was approved by the FDA on January 10, 2022, under the name QUVIVIQ. as the second orexin receptor antagonist approved to treat insomnia following suvorexant. Daridorexant was approved by the European Commission on May 3, 2022, as the first dual orexin receptor antagonist approved in the market, and by Health Canada on April 26, 2023.

In the US and Europe, daridorexant is indicated for the treatment of adult patients with insomnia characterized by difficulties with sleep onset and/or sleep maintenance. The European prescribing information states that insomnia should be characterized by symptoms that are present for at least three months and have a considerable impact on daytime functioning.