
Merck has agreed to acquire biopharmaceutical company Verona Pharma in a deal valued at $10bn.
The acquisition will be made by the subsidiary of Merck, which is known as MSD outside of the US and Canada.
The transaction will enhance Merck’s cardio-pulmonary pipeline and portfolio with the addition of Ohtuvayre (ensifentrine), an FDA-approved treatment for chronic obstructive pulmonary disease (COPD) in adults.
The deal has received support from both companies’ boards of directors and is expected to close in the fourth quarter (Q4) of 2025.
The completion of the acquisition hinges on approvals including antitrust clearance under the Hart-Scott-Rodino Antitrust Improvements (HSR) Act, endorsement from Verona Pharma shareholders and approval by the High Court of Justice in England and Wales.
Upon finalisation, most of the purchase price will be capitalised as an intangible asset for Ohtuvayre, which will then be amortised as a generally accepted accounting principles (GAAP)-only charge over the product’s lifespan.

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By GlobalDataMerck chairman and CEO Robert M Davis stated: “This acquisition of Verona Pharma reflects the commitment we have to delivering innovative treatments to patients and our ability to execute on our science-led and value-driven business development strategy.
“Ohtuvayre complements and expands our pipeline and portfolio of treatments for cardio-pulmonary diseases while delivering near and long-term growth as well as value for shareholders. This novel, first-in-class treatment addresses an important unmet need for COPD patients persistently symptomatic based on its unique combination of bronchodilatory and non-steroidal anti-inflammatory effects. We look forward to welcoming the talented Verona Pharma team to Merck.”
Ohtuvayre, a first-in-class selective dual inhibitor of phosphodiesterase 3 and 4 (PDE3 and PDE4), is the first novel inhaled mechanism for treating COPD in more than 20 years. It offers combined bronchodilator and non-steroidal anti-inflammatory effects.
Clinical trials are also underway to evaluate its efficacy in treating non-cystic fibrosis bronchiectasis.
Citi and Morgan Stanley acted as financial advisors for Merck while Freshfields provided legal counsel. Centerview Partners served as exclusive financial advisor to Verona Pharma with Latham & Watkins offering legal advice.
Verona Pharma president and CEO David Zaccardelli stated: “Today’s announced agreement with Merck is the culmination of years of focus and determination by the Verona Pharma team advancing Ohtuvayre, the first novel inhaled mechanism for the maintenance treatment of COPD in two decades.
“Since launching Ohtuvayre in August 2024, we have seen rapid and accelerating uptake in the US. We believe Merck’s commercial footprint and industry-leading clinical capabilities will help accelerate the potential of Ohtuvayre to reach more patients living with COPD. This agreement will enable the strong launch trajectory of this important medicine and provides value to Verona Pharma shareholders.”
Keytruda, which brought in $30bn in revenue in 2024, is approaching patent expirations set in 2028, and Merck is therefore intensifying efforts to restructure its portfolio, according to a report by Reuters.
The acquisition is Merck’s first of 2025 and is its largest since the $10.8bn acquisition of Prometheus Biosciences in 2023.