DNL.L Regulatory News (DNL)

13 September 2021

Diurnal Group plc

("Diurnal" or the "Company")

Commercial launch of Efmody® in the UK

Follows recent European launch in Germany and Austria

Provides a new treatment option for adult and adolescent patients suffering from CAH in the UK

Diurnal Group plc (AIM: DNL), the specialty pharmaceutical company targeting patient needs in chronic endocrine (hormonal) diseases, announces the commercial launch of Efmody® (hydrocortisone modified-release hard capsules) in the United Kingdom as treatment of adult and adolescent patients (12 years and older) with the rare condition congenital adrenal hyperplasia (CAH). The launch of Efmody® follows its approval by the UK Medicines and Healthcare Products Regulatory Agency (MHRA) in Great Britain (England, Wales and Scotland) in July 2021.

Consistent with the Company's European commercialisation strategy, Diurnal is marketing Efmody® in the UK with its own salesforce. In parallel to this launch and following the recent launch in Germany and Austria on 1 September, Diurnal is currently in discussions with various health authorities across the European Economic Area to ensure timely launches in other major European countries. Launch stocks of Efmody® have been manufactured in advance of the planned launches in order to provide timely availability of the product, utilising many aspects of the supply chain that have already been established by the Company for Alkindi®.

Efmody® is a preparation of hydrocortisone that has been specifically designed for patients with CAH, a rare condition caused by deficiency of adrenal enzymes, most commonly 21-hydroxylase. 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 5,000 patients in Great Britain.

Martin Whitaker, Chief Executive Officer of Diurnal, commented:

"We are delighted to have launched Efmody® in the UK. Efmody® provides a new treatment option for patients suffering with CAH in Great Britain, and we look forward to being able to provide Efmody® to these patients."

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 a rare 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 41,000 patients in Europe and Great Britain, with over 400,000 in the rest of the world.

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 MHRA and European Commission marketing authorisation approval of Efmody® was based on a Phase 3 study conducted in a total of 122 patients enrolled across 11 clinical sites, including sites in Great Britain, 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 5 years. Summary of Product Characteristics (SmPC) for UK (Northern Ireland) can be found here.

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

Date of Preparation: September 2021 Code: CORP-GB-0149