The contents of this Report on Form
6-K (excluding Exhibit 99.1 hereto) are incorporated by reference in the Companys registration statement on Form F-3 (File
No. 333-258495).
About AATD-LD
Alpha-1 antitrypsin deficiency is a genetic condition that results in progressive
alveolar destruction leading to emphysema. People with alpha-1 antitrypsin deficiency have significantly reduced levels of AAT, a protective protein that inhibits the protease, neutrophil elastase. Unopposed
neutrophil elastase is believed to the key enzyme in the causal pathologic pathway of AATD-LD. AATD-LD presents at age 20 to 50 with symptoms including, shortness of
breath, cough, and reduced exercise tolerance. People with AATD may progress to chronic oxygen therapy, lung surgery, transplant, and death.
About
Alvelestat
Alvelestat (MPH-966) is a novel, oral small molecule designed to
inhibit neutrophil elastase, a key enzyme involved in the destruction of lung tissue. Prior to Mereo BioPharma licensing alvelestat from AstraZeneca (AZ), trials across COPD, bronchiectasis and cystic fibrosis (CF) had been performed. Over 1,000
subjects were exposed to alvelestat, with signals of efficacy in both bronchiectasis and CF. Statistically significant reduction in urine desmosine was seen in the CF trial and an improvement in Forced Expiratory Volume in 1 second (FEV1) of 100ml vs placebo in the bronchiectasis trial. Alvelestat is also under clinical investigation in an ongoing Phase 1b/2 investigator-sponsored study Bronchiolitis Obliterans Syndrome (BOS)
following allogeneic hematopoietic stem cell transplant. Interim data from the phase 1b portion of the study showed progressive reduction of plasma desmosine over 8 weeks in 6 of 7 treated patients, all of whom had improved or stable lung disease
(FEV1) and reduction in stimulated neutrophil elastase activity and fibrosis biomarkers. Mereo reported a positive Phase 1b/2 trial in COVID-19 which was
completed in 2021 and showed alvelestat was safe and well tolerated. Alvelestat on top of standard of care resulted in a more rapid time to improvement in WHO Disease Severity score of >=2 in the first 5-7
days compared to placebo plus standard of care.
About Mereo BioPharma Group plc
Mereo BioPharma Group plc is a biopharmaceutical company focused on the development of innovative therapeutics that aim to
improve outcomes for oncology and rare diseases and plans to commercialize selected rare disease programs. The Company has developed a portfolio of six clinical stage product candidates. Mereos lead oncology product candidate, etigilimab
(anti-TIGIT), has advanced into an open label Phase 1b/2 basket study evaluating anti-TIGIT in combination with an anti-PD-1 in a range of tumor types including three
rare tumors and three gynecological carcinomas, cervical, ovarian, and endometrial carcinomas. The Companys second oncology product, navicixizumab, for the treatment of late line ovarian cancer, has completed a Phase 1 study and has been
partnered with OncXerna Therapeutics, Inc., formerly Oncologie, Inc. The Company has two rare disease product candidates, alvelestat for the treatment of severe Alpha-1 antitrypsin deficiency (AATD) and
Bronchiolitis Obliterans Syndrome (BOS), and setrusumab for the treatment of osteogenesis imperfecta (OI). Alvelestat has recently received U.S. Orphan Drug Designation for the treatment of AATD and positive
top-line data were recently reported from a Phase 2 proof-of-concept study in North America, Europe and the UK. The
Companys partner, Ultragenyx Pharmaceutical, Inc., has initiated a pivotal Phase 2/3 pediatric study in young adults (5-25 years old) for setrusumab in OI and expects to initiate a study in pediatric
patients (2-5 years old) in the second half of 2022.
Forward-Looking Statements
This Report on Form 6-K contains forward-looking statements. All
statements other than statements of historical fact contained herein are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the Securities Act), and Section 21E of the
Securities Exchange Act of 1934, as amended (the Exchange Act). Forward-looking statements usually relate to future events and anticipated revenues, earnings, cash flows or other aspects of our operations or operating results.
Forward-looking statements are often identified by the words believe, expect, anticipate, plan, intend, foresee, should, would, could,
may, estimate, outlook and similar expressions, including the negative thereof. The absence of these words, however, does not mean that the statements are not forward-looking. These forward-looking statements are
based on the Companys current expectations, beliefs and assumptions concerning future developments and business conditions and their potential effect on the Company. While management believes that these forward-looking statements are
reasonable as and when made, there can be no assurance that future developments affecting the Company will be those that it anticipates.