MPH.L Regulatory News (MPH)

Mereo BioPharma Group plc

("Mereo" or the "Company" or the "Group")

BGS-649 Phase 2b data to be Presented at ENDO 2019

London, 15 January 2019 - Mereo BioPharma Group plc (AIM: MPH), a clinical stage, UK-based, biopharmaceutical company focused on rare and specialty diseases, is pleased to announce that the abstract, entitled 'Beneficial Effect on Sperm Production of Leflutrozole in Men with Obesity-Associated Secondary Hypogonadotropic Hypogonadism: Results from a Phase II Study' will be presented by Professor Hugh Jones, Barnsley Hospital NHS Foundation Trust and the University of Sheffield at ENDO 2019 in New Orleans, LA on 24 March 2019 from 10.00am to 12.00pm CST.

The oral presentation will focus on sperm production data from Mereo's Phase 2b in men with obesity-associated secondary hypogonadotropic hypogonadism.

The title, timing and location of the presentation is as follows:

Abstracts will be published online no later than 31 January 2019. You may view the abstract after 31 January by searching for Mereo on the ENDO web program at https://www.abstractsonline.com/pp8/#!/5752

About Hypogonadotropic Hypogonadism

Hypogonadotropic hypogonadism results from inadequate levels of testosterone. Symptoms associated with testosterone deficiency include reduced/loss of libido, erectile dysfunction, tiredness, fatigue, impaired physical endurance, loss of vitality, lack of motivation and mood disturbance. There are approximately seven million cases of HH in obese men in the US and approximately five million cases in Europe. Current therapies for HH involve direct replacement of testosterone administered by gel formulations applied to the skin, which risk transference to anyone in close contact, patches or intramuscular injections, which can be painful and inconvenient. Direct exogenous testosterone replacement can also impair male fertility by suppressing LH and FSH.

About BGS-649

BGS-649 is a once a week oral treatment for HH in obese men, that restores a patient's own testosterone. It is a novel aromatase inhibitor that inhibits conversion of the patients' own testosterone to oestradiol, thereby increasing testosterone levels. BGS-649 is designed to be more convenient compared with current therapies and due to its mechanism of action restores normal testosterone production without the risk of supra-physiological levels or suppression of LH and FSH, thereby treating the symptoms of HH whilst maintaining or improving testicular function.

About Mereo

Mereo is a biopharmaceutical company focused on the development and commercialization of innovative therapeutics that aim to improve outcomes for patients with rare diseases. Mereo's strategy is to selectively acquire product candidates that have already received significant investment from pharmaceutical companies and that have substantial preclinical, clinical and manufacturing data packages. In December 2018, Mereo announced the proposed combination of Mereo and OncoMed Pharmaceuticals Inc., with the transaction expected to close in the first half of 2019. Each of Mereo's four product candidates has previously generated positive clinical data for Mereo's target indication or in a related indication. Since inception Mereo has commenced large, randomized, placebo-controlled Phase 2 clinical trials for all four of the product candidates:

· BPS-804 for osteogenesis imperfecta (OI). The Company recently announced completion of enrolment with 112 adult patients in a Phase 2b dose ranging study with some initial data expected in the H1 2019 and top-line dose ranging data in late 2019. A pediatric Phase 3 study design has also been approved by the EMA. BPS-804 has orphan designation in the US and EU and has been accepted into the PRIME and Adaptive Pathways in EU;

· MPH-966 for alpha-1 antitrypsin deficiency (AATD). The Company recently announced first patient in in a Phase 2 dose ranging study in the US with data expected in late 2019;

· BCT-197 for acute exacerbations of COPD (AECOPD). The Company presented positive Phase 2 data at the American Thoracic Society in May, 2018;

· BGS-649 for hypogonadotropic hypogonadism (HH). The Company announced positive top-line Phase 2b data in March 2018. Positive data from the safety extension study to the Phase2b clinical trial was announced in December 2018; and

· As at September 30, 2018 Mereo had (unaudited) total cash resources of approximately US$44.6 million

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