Merck & Co. has agreed to acquire Acceleron Pharma for US$180 per share which represents a total transaction value of US$11.5 B. With the deal, Merck gains access to Acceleron’s lead candidate, sotatercept, which is indicated in patients with pulmonary arterial hypertension. The deal is line with Merck’s attempt towards diversifying its pipeline beyond Keytruda® (pembrolizumab) as it nears loss of exclusivity in 2028. Merck also expands its rare disease portfolio with the addition of Reblozyl® (luspatercept).