Diurnal (DNL) is a commercial-stage specialty pharmaceutical company focused on diseases of the endocrine system. Its two lead products target rare conditions where medical needs are currently unmet, with the aim of building a long-term ‘Adrenal Franchise’. Alkindi is being launched in key EU markets, and this was expected to be followed by Chronocort. However, DNL has received the headline data from its European Phase III trial in CAH, which showed that Chronocort was not superior to standard-of-care, thereby failing to meet its primary end-point. Given the strong Phase II data, this outcome was unexpected. The full data set is now being analysed.