Pharmaceutical Mergers and Acquisitions in Crisis and Non-Crisis Periods: Effects on Shareholder Value Creation Evidence from the United States and Europe

Sammanfattning

This thesis examines whether pharmaceutical acquisitions announced during macroeconomic crisis periods are associated with different abnormal returns than acquisitions announced during non-crisis periods, and whether these effects differ betweenU.S. and European acquirers. Using a sample of 135 completed pharmaceutical-topharmaceutical acquisitions announced between 2005 and 2025, the study applies adual-horizon event study framework based on cumulative abnormal returns (CAR)and buy-and-hold abnormal returns (BHAR).The findings show that crisis-period acquisitions are associated with more favorable short-term abnormal returns for U.S. acquirers, particularly in the CAR(−3,+3)window. In contrast, the corresponding effects for European acquirers are consistentlyweaker than those observed for U.S. acquirers and are not statistically distinguishablefrom zero in net-effect tests. The long-term BHAR results provide no consistentevidence of persistent abnormal performance and remain sensitive to methodologicalspecification.The analysis further shows no statistically significant differences across crisistypes. Overall, the findings suggest that favorable market reactions to pharmaceuticalacquisitions during crisis periods are short-term, institutionally dependent, andconcentrated in specific transaction settings rather than reflecting broad or persistentshareholder value creation.