Merck has agreed to acquire London-based Verona Pharma for $10 billion, acquiring the FDA-approved inhaled therapy Ohtuvayre (ensifentrine) for chronic obstructive pulmonary disease (COPD). This first-in-class drug combines bronchodilator and anti-inflammatory mechanisms, representing the first inhaled therapy with a novel mode of action for COPD in over two decades. Early commercial performance is strong, with $71 million in Q1 2025 sales and forecasts exceeding $4 billion in peak sales. The deal, Merck's largest since its 2023 Prometheus acquisition, marks a significant expansion in its cardiopulmonary pipeline as Keytruda faces patent expirations. Verona is also conducting trials of ensifentrine for other respiratory conditions such as asthma and bronchiectasis.