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.

Merck & Co. agreed to buy respiratory drugmaker Verona Pharma Plc for around $10 billion as part of its ongoing search for ways to fill the Keytruda-sized hole that will emerge over the next few years.

The move bolsters Merck’s lineup as it braces for the 2028 loss of patent exclusivity for blockbuster cancer drug Keytruda.