Suvorexant (Belsomra(®)), a first-in-class, orally active dual orexin-1 receptor and orexin-2 receptor antagonist, has been developed by Merck for the treatment of insomnia. Variations in the levels of the neuropeptides orexin A and orexin B have been linked to circadian rhythms and wakefulness. Orexin-producing neurons in the lateral hypothalamus regulate wakefulness by signalling through orexin receptors. Blockade of orexin receptors is known to promote sleep. Suvorexant was approved in the US in August 2014 for the treatment of adults with sleep onset and/or sleep maintenance insomnia. The drug is also preregistration in Japan, with approval submissions planned for other countries worldwide for this indication. This article summarizes the milestones in the development of suvorexant leading to this first approval for insomnia.