Merck plans to buy Terns Pharmaceuticals for $6.7 billion. Terns Pharmaceuticals is developing a promising treatment for leukemia. The article also mentions the rise of former Loxo executives at Lilly. Terns Pharmaceuticals to Present 2026 Program Priorities and Milestones at J.P. 44th Annual Conference Morgan Healthcare Conference. Keytruda from Merck & Co. (active substance pembrolizumab) is the most profitable drug in the world. It is a biologic drug, a monoclonal antibody made from living cells that is not easily imitated by generic versions.