Merck to Acquire Verona Pharma in $10 Billion Deal, Adding Ohtuvayre® to Strengthen Respiratory Portfolio and Expand Long-Term Growth in COPD Market
Merck & Co., known as MSD outside the U.S. and Canada, today announced a definitive agreement to acquire Verona Pharma plc (Nasdaq: VRNA), a biopharmaceutical company specializing in respiratory diseases. Under the terms of the agreement, Merck, through a subsidiary, will acquire all outstanding shares of Verona Pharma for $107 per American Depositary Share (ADS) — each ADS representing eight ordinary shares of Verona Pharma — in a deal valued at approximately $10 billion.
This strategic acquisition is set to bolster Merck’s presence in the rapidly evolving cardio-pulmonary therapeutic area, adding the recently FDA-approved Ohtuvayre® (ensifentrine) to its portfolio. The transaction has been unanimously approved by the Boards of Directors of both companies and is expected to close in the fourth quarter of 2025, pending customary closing conditions and regulatory approvals.
Ohtuvayre: A First-in-Class COPD Maintenance Therapy
Ohtuvayre (ensifentrine) is a first-in-class selective dual inhibitor of phosphodiesterase 3 and 4 (PDE3 and PDE4). In June 2024, the U.S. Food and Drug Administration (FDA) approved Ohtuvayre as a maintenance treatment for adults with chronic obstructive pulmonary disease (COPD) — marking the first novel inhaled mechanism approved for COPD in over 20 years.
The therapy offers a dual-action mechanism, providing both bronchodilator effects and non-steroidal anti-inflammatory benefits, positioning it as a significant advancement for patients who remain symptomatic despite existing treatments. Ohtuvayre is also currently being studied in clinical trials for non-cystic fibrosis bronchiectasis, highlighting its potential to address a broader range of respiratory conditions.
Merck: Expanding Capabilities in Respiratory Medicine
“This acquisition of Verona Pharma demonstrates our commitment to delivering innovative therapies that address unmet medical needs,” said Robert M. Davis, Chairman and Chief Executive Officer of Merck. “Ohtuvayre is a differentiated therapy with a unique mechanism of action that expands our cardio-pulmonary pipeline. It not only strengthens our existing portfolio but also offers near- and long-term growth potential, aligning with our strategy to build a scientifically-driven and patient-focused business.”
Davis emphasized that the addition of Ohtuvayre supports Merck’s long-term objectives, particularly in light of the increasing global burden of COPD, a progressive and debilitating respiratory condition affecting millions worldwide
Verona Pharma: Transitioning a Breakthrough Therapy
“We are proud of the work our team has done to bring Ohtuvayre to market,” said David Zaccardelli, President and CEO of Verona Pharma. “The agreement with Merck reflects the value we’ve created and provides a powerful opportunity to accelerate the reach and impact of Ohtuvayre.”
Since the U.S. launch in August 2024, Ohtuvayre has experienced strong and accelerating adoption, reinforcing its potential to become a standard of care in COPD maintenance. Zaccardelli noted that Merck’s global commercial infrastructure and clinical development capabilities are ideally suited to support the continued growth and lifecycle expansion of the product.
Transaction Details and Structure
- Valuation: $107 per ADS, representing an equity value of approximately $10 billion.
- Structure: The acquisition will be carried out via a UK court-sanctioned scheme of arrangement, consistent with UK corporate law.
- Regulatory Review: Closing is contingent upon regulatory clearance under the Hart-Scott-Rodino Antitrust Improvements Act, shareholder approval by Verona Pharma investors, sanction by the High Court of Justice of England and Wales, and other customary closing conditions.
- Accounting: The acquisition will result in the capitalization of most of the purchase price as an intangible asset associated with Ohtuvayre, which Merck expects to amortize over the product’s commercial lifecycle as a GAAP-only charge.
Investor Communications
Merck will host a live investor call to discuss the transaction on Tuesday, July 9, 2025, at 8:00 a.m. ET.
Participants may join via webcast or by dialing:
- U.S. & Canada Toll-Free: (800) 369-3351
- International Dial-In: (517) 308-9448
- Access Code: 2398172
The webcast will also be available for replay on Merck’s investor relations website. Journalists may contact Merck’s media relations team following the call with questions or interview requests.
Legal and Financial Advisors
- Merck’s Financial Advisors: Citi and Morgan Stanley & Co. LLC
- Merck’s Legal Counsel: Freshfields LLP
- Verona Pharma’s Financial Advisor: Centerview Partners LLC
- Verona Pharma’s Legal Counsel: Latham & Watkins LLP
Ohtuvayre Indication and Safety Information
INDICATION
Ohtuvayre (ensifentrine) is indicated for the maintenance treatment of COPD in adult patients. It is not intended for acute symptom relief.
IMPORTANT SAFETY INFORMATION
Contraindications
- Hypersensitivity to ensifentrine or any component of the formulation.
Warnings and Precautions
- Not for Acute Use: Ohtuvayre is not suitable as a rescue therapy for acute bronchospasm episodes. A short-acting bronchodilator should be used for immediate relief.
- Paradoxical Bronchospasm: May occur and could be life-threatening. If symptoms arise, treatment should be discontinued and alternative therapies initiated.
- Psychiatric Risks: Psychiatric adverse events, including insomnia, anxiety, and suicidality, have been observed. Healthcare providers should weigh risks in patients with a history of depression or suicidal behavior and monitor closely during treatment.
Psychiatric Adverse Event Data (Pooled 24-Week Safety Population):
- Insomnia: 0.6% in Ohtuvayre (3 mg) group vs. 0.3% placebo
- Anxiety: 0.2% Ohtuvayre vs. 0.2% placebo
- Depression-related events: 0.4% Ohtuvayre; 0% placebo
- Suicide-related adverse events: 1 suicide attempt and 1 suicide in the Ohtuvayre group during trials
Common Adverse Reactions (≥1%)
- Back pain: 1.8%
- Hypertension: 1.7%
- Urinary tract infection: 1.3%
- Diarrhea: 1.0%
Full prescribing information is available on the Ohtuvayre website and through the FDA.
About Merck
Merck, known as MSD outside the U.S. and Canada, is a global healthcare leader working to help the world be well. For over 130 years, Merck has brought hope to humanity through the development of important medicines and vaccines. Merck continues to lead in oncology, infectious diseases, vaccines, cardio-metabolic disorders, and emerging therapeutic areas.
About Verona Pharma
Verona Pharma plc is a clinical-stage biopharmaceutical company dedicated to developing innovative therapies for respiratory diseases. The company’s lead asset, Ohtuvayre, was developed to address the limitations of current treatments in COPD and other chronic airway conditions.
