Merck said on Wednesday it will acquire UK-based Verona Pharma for about $10 billion, gaining a promising respiratory treatment as it faces pressure to diversify beyond its blockbuster cancer drug Keytruda.

Verona Pharma brings to Merck the inhaled drug Ohtuvayre, which is FDA approved as a treatment for chronic obstructive pulmonary disease. While Ohtuvayre is projected to become a blockbuster product in COPD alone,