Company Description
Mereo BioPharma Group plc (NASDAQ: MREO) is a clinical-stage biopharmaceutical company focused on the development of therapeutics for rare diseases. According to the company’s public disclosures, Mereo is advancing a pipeline that includes rare disease product candidates for bone and lung disorders, as well as partnered programs in oncology and reproductive medicine.
Rare disease focus and core programs
Mereo states that it has three rare disease product candidates: setrusumab for the treatment of osteogenesis imperfecta (OI), alvelestat for the treatment of alpha-1 antitrypsin deficiency-associated lung disease (AATD-LD), and vantictumab for the treatment of autosomal dominant osteopetrosis type 2 (ADO2). The company describes itself as a clinical-stage organization, with late-stage clinical development activities centered on these programs.
Setrusumab (UX143) is described as a fully human monoclonal antibody that inhibits sclerostin, a negative regulator of bone formation. Mereo reports that setrusumab is being developed for OI through a partnership with Ultragenyx Pharmaceutical Inc. Publicly available information notes that Ultragenyx has led a pivotal Phase 2/3 Orbit study in pediatric and young adult patients with OI and a Phase 3 Cosmic study in younger pediatric patients. The company has disclosed that Phase 3 Orbit and Cosmic studies did not achieve statistical significance on primary fracture endpoints but did show statistically significant improvements in bone mineral density compared with comparators, with a safety profile consistent with prior studies.
Alvelestat (also referred to as MPH-966) is described as an oral neutrophil elastase inhibitor being studied for AATD-LD. Mereo reports that it has aligned with the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) on primary endpoints for a planned single global Phase 3 pivotal study in early- and late-stage AATD-LD patients. The company has indicated that it is in active discussions with potential partners for Phase 3 development and commercialization of alvelestat.
Vantictumab is described as a monoclonal antibody that selectively binds to certain frizzled receptors and inhibits Wnt signaling pathways. Mereo reports that vantictumab was previously investigated in oncology settings and has been out-licensed to āshibio, Inc. for the treatment of ADO2, while Mereo has retained commercial rights in Europe. According to company and partner disclosures, āshibio is responsible for funding the global development program and has reported preclinical data in an ADO2 mouse model.
Partnerships and geographic rights
Mereo’s disclosures emphasize a partnership-driven model for several of its assets. For setrusumab, the company reports that Ultragenyx funds global development and that the collaboration includes potential additional milestone payments of up to $245 million and royalties to Mereo on commercial sales in Ultragenyx territories. Mereo states that it has retained commercial rights in the European Union and the United Kingdom for setrusumab and will pay Ultragenyx royalties on commercial sales in those territories.
For vantictumab, Mereo has granted āshibio an exclusive license to develop and commercialize the asset in the United States and the rest of the world, excluding Europe, where Mereo retains commercial rights. The company also reports a global license agreement with ReproNovo SA for leflutrozole, a non-steroidal aromatase inhibitor for the treatment of infertility in men with low testosterone, and a global licensing agreement with Feng Biosciences, Inc. for navicixizumab, an oncology product candidate for the potential treatment of late-line ovarian cancer.
Regulatory designations
Mereo highlights several regulatory designations for its rare disease programs. Public statements note that setrusumab has received orphan designation for OI from the European Commission and the FDA, PRIME designation from the EMA, and Breakthrough Therapy and rare pediatric disease designations from the FDA. For alvelestat, the company reports Orphan Designation for AATD from the European Commission and the FDA, and Fast Track designation from the FDA for AATD-LD. Mereo has also disclosed a positive EMA opinion and subsequent European Commission Orphan Designation decision for alvelestat for AATD-LD.
Additional pipeline programs
Beyond its rare disease assets, Mereo reports two oncology product candidates: etigilimab, described as an anti-TIGIT antibody, and navicixizumab, which is being evaluated for the potential treatment of late-line ovarian cancer and is partnered with Feng Biosciences, Inc. The company also notes its exclusive global license agreement with ReproNovo SA covering leflutrozole.
Stock listing and corporate profile
Mereo BioPharma Group plc is incorporated in England and Wales and reports its principal executive offices in London, United Kingdom. The company’s ordinary shares have a nominal value of £0.003 per share, and American Depositary Shares (ADSs) representing its ordinary shares are listed on The Nasdaq Stock Market LLC under the symbol MREO, as reflected in its SEC filings. The company describes itself consistently in news releases and filings as a clinical-stage biopharmaceutical company focused on rare diseases.
How Mereo BioPharma fits within biotechnology
Based on its public disclosures, Mereo operates in the biopharmaceutical segment of the biotechnology industry with a focus on rare diseases affecting bone and lung function, as well as partnered programs in oncology and reproductive health. Its business model, as described by the company, combines internal clinical development with collaborations and licensing agreements for global or regional rights, milestone payments, and potential royalties.
Stock Performance
Mereo Biopharma (MREO) stock last traded at $0.3420, down 9.76% from the previous close. Over the past 12 months, the stock has lost 86.6%. At a market capitalization of $57.4M, MREO is classified as a micro-cap stock with approximately 159.1M shares outstanding.
Latest News
Mereo Biopharma has 10 recent news articles, with the latest published 2 days ago. Of the recent coverage, 6 articles coincided with positive price movement and 4 with negative movement. Key topics include earnings, clinical trial, conferences. View all MREO news →
SEC Filings
Mereo Biopharma has filed 5 recent SEC filings, including 3 Form 4, 1 Form 10-K, 1 Form 8-K. The most recent filing was submitted on March 19, 2026. SEC filings provide transparency into a company's financial condition, material events, and regulatory compliance. View all MREO SEC filings →
Financial Highlights
Mereo Biopharma generated $1.0M in revenue over the trailing twelve months, retaining a 90.0% gross margin, operating income reached -$40.1M (-4010.7% operating margin), and net income was -$41.9M, reflecting a -4187.8% net profit margin. Diluted earnings per share stood at $-0.05. The company generated -$31.0M in operating cash flow. With a current ratio of 10.46, the balance sheet reflects a strong liquidity position.
Upcoming Events
Vantictumab Phase 2 planned
Vantictumab Phase 2 start
Cash runway through mid-2027
Mereo Biopharma has 3 upcoming scheduled events. The next event, "Vantictumab Phase 2 planned", is scheduled for July 1, 2026 (in 101 days). 1 of the upcoming events are financial in nature, such as earnings calls or quarterly results. Investors can track these dates to stay informed about potential catalysts that may affect the MREO stock price.
Short Interest History
Short interest in Mereo Biopharma (MREO) currently stands at 13.0 million shares, up 32.9% from the previous reporting period, representing 8.3% of the float. Over the past 12 months, short interest has increased by 99.3%.
Days to Cover History
Days to cover for Mereo Biopharma (MREO) currently stands at 1.5 days, up 50% from the previous period. This low days-to-cover ratio indicates high liquidity, allowing short sellers to quickly exit positions if needed. The days to cover has decreased 75.6% over the past year, suggesting improved liquidity for short covering. The ratio has shown significant volatility over the period, ranging from 1.0 to 12.7 days.
MREO Company Profile & Sector Positioning
Mereo Biopharma (MREO) operates in the Biotechnology industry within the broader Pharmaceutical Preparations sector and is listed on the NASDAQ.
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