Planned Acquisition of Acceleron Bolsters Innovation and Broadens Cardiovascular Pipeline Merck announced a definitive agreement and tender offer to acquire Acceleron Pharma Inc. (Acceleron). The planned acquisition complements and strengthens Merck's cardiovascular pipeline with Acceleron's lead therapeutic candidate, sotatercept, a potentially first-in-class therapy in Phase 3 clinical trials for the treatment of pulmonary arterial hypertension. Merck commenced a tender offer on Oct. 12, 2021, and upon successful completion of the tender offer and receipt of necessary regulatory approvals, Merck, through a subsidiary, will acquire Acceleron for $180 per share in cash for an approximate total equity value of $11.5 billion.