1 June 2021

Diurnal Group plc

("Diurnal" or the "Company")

Diurnal triggers $1.25m in milestone payments from Citrine Medicine

Diurnal Group plc (AIM: DNL), the specialty pharmaceutical company targeting patient needs in chronic endocrine (hormonal) diseases, announces that it has triggered payments totalling $1.25 million from Citrine Medicine, Inc. ("Citrine"), its partner in China, relating to the recent European Commission's (EC) approval for Efmody^® (hydrocortisone modified-release hard capsules) and the attainment by Citrine of certain development milestones in China for Alkindi^® (hydrocortisone granules in capsules for opening). Citrine continues to plan for a New Drug Application (NDA) submission to the National Medical Products Administration in 2021 for Alkindi^®.

Citrine is a therapeutics platform company focused on the Greater China market that has licensed the registration and commercialisation rights for Alkindi^® and Efmody^® in China, Hong Kong, Taiwan and Macau. Today's announcement follows the Company extending its exclusive license agreement with Citrine in May 2021 to cover Efmody^® and subsequently receiving an upfront payment of $1.0 million.

This is a business press release containing financial information and/or data for the benefit of shareholders and potential investors. Data are included to allow informed investment decisions.

This announcement contains inside information for the purposes of Article 7 of Regulation (EU) 596/2014 (MAR).

Notes to Editors

About Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia (CAH) is an orphan condition caused by deficiency of adrenal enzymes, most commonly 21-hydroxylase. This enzyme is required to produce the adrenal steroid hormone, cortisol. The block in the cortisol production pathway causes the over-production of male steroid hormones (androgens), which are precursors to cortisol. The condition is congenital (inherited at birth) and affects both sexes. The cortisol deficiency and over-production of male sex hormones can lead to increased mortality, infertility and issues during sexual development including ambiguous genitalia, premature (precocious) sexual development and short stature. Sufferers, even if treated, remain at risk of death through an adrenal crisis.

Current therapy for CAH uses a variety of generic glucocorticoid (steroids including hydrocortisone, dexamethasone, prednisolone and prednisone in the US) with no standard treatment regimen. Approximately two-thirds of CAH patients are estimated to have poor disease control, leading to elevated androgen levels. The condition is estimated to affect a total of approximately 400,000 patients worldwide.  

About Alkindi^® (hydrocortisone granules in capsules for opening)

Alkindi^® is the first preparation of hydrocortisone specifically designed for use in children suffering from paediatric adrenal insufficiency (AI), including congenital adrenal hyperplasia (CAH). Alkindi^® is a patented, oral, immediate-release paediatric formulation of hydrocortisone granules in capsules for opening that allows for accurate age-appropriate dosing in children. This therapeutic approach has the potential to help young patients less than eighteen years of age suffering from diseases due to cortisol deficiency including paediatric AI and CAH. AI requires life-long treatment and Diurnal's novel approach to product development has the potential to significantly improve these young patients' lives. The European Commission has granted a paediatric use marketing authorisation (PUMA) for Alkindi^® as replacement therapy of AI in infants, children and adolescents (from birth to <18 years old) in Europe. Alkindi^® is approved and known as Alkindi^® Sprinkle in the US where it is licensed and marketed by Eton Pharmaceuticals. Alkindi^® is also approved in Israel and Australia.

About Efmody^® (hydrocortisone modified-release hard capsules)

Efmody^® is a preparation of hydrocortisone that has been specifically designed to mimic the circadian rhythm of cortisol when given in a twice-a-day "toothbrush" regimen (administered last thing at night before sleep and first thing in the morning on waking) to control androgen excess and chronic fatigue in patients with diseases of cortisol deficiency. The first indication for Efmody^® is Congenital Adrenal Hyperplasia (CAH) in adults and adolescents (children older than 12 years of age). Efmody^® has been extensively studied in 239 human subjects including 138 CAH patients who have taken part in clinical trials in Europe and the US.

The EC registration of Efmody is based on a Phase 3 study conducted in a total of 122 patients enrolled across 11 clinical sites, the largest ever interventional clinical trial completed in CAH. The Phase 3 data was supported by detailed analysis of data from an open-label safety extension study for patients completing treatment in the Phase 3 study, which is assessing the impact of treatment with Efmody^® over an extended period, with a number of patients on this trial having been treated for over 54 months. Patient retention rates in this study have been high and patients on this trial have, to date, shown sustained benefit from extended Efmody^® treatment.

About Diurnal Group plc

Diurnal Group plc is a European, UK-headquartered, specialty pharmaceutical company dedicated to developing hormone therapeutics to aid lifelong treatment for rare and chronic endocrine conditions, including congenital adrenal hyperplasia, adrenal insufficiency, hypogonadism and hypothyroidism. Its expertise and innovative research activities focus on circadian-based endocrinology to yield novel product candidates in the rare and chronic endocrine disease arena.

For further information about Diurnal, please visit www.diurnal.co.uk

About Citrine Medicine

Citrine Medicine is dedicated to improving the lives of patients with rare and intractable diseases by making diagnosis and essential treatments available and accessible to those who need them in China. Our mission is to build the first rare disease ecosystem in China and in doing so, enable people with rare diseases to live more normal lives. In addition to developing and marketing rare disease drugs, Citrine aims to establish a patient-centric platform which educates people on rare diseases, trains doctors on diagnosis and treatment, and helps doctors develop a full disease management protocol. Citrine's lead product candidate, Wakix^® (pitolisant), is an investigational oral drug in development for the treatment of narcolepsy and obstructive sleep apnea in China. Citrine has initiated an Investigational New Drug (IND) submission for pitolisant in the treatment of narcolepsy and expects to complete the IND submission in the first quarter of 2021. Citrine also recently announced a strategic partnership that will allow the company exclusive rights to develop, register, and commercialize Alkindi^® - the first clinically validated pediatric treatment for congenital adrenal hyperplasia - in the Greater China market. Citrine is headquartered in Shanghai and has other offices in Beijing, China and Cambridge, Mass.

For further information about Citrine Medicine, please visit www.citrinemed.com 

Date of Preparation: June 2021              Code: CORP-GB-0127