Trouble builds for Merck's $11.5B Acceleron buy as activist investor behind Gilead's Immunomedics deal says too early, too cheap

Merck hopes its $11.5 billion Acceleron buy will quickly wrap up in the fourth quarter. But revolt from an activist investor threatens to derail that plan. Hours after Merck’s Thursday announcement, Avoro Capital slammed the New Jersey pharma’s $180-apiece price, arguing it “drastically undervalues” Acceleron. The investment shop owns about 7% of Acceleron shares.