After a banner year in 2021, Pfizer (NYSE:PFE) is on a spending spree. The company plans to acquire Global Blood Therapeutics (GBT) (Nasdaq:GBT) for $68.50 per share. The total sale price of acquisition, if it moves forward, would be roughly $5.4 billion. Global Blood Therapeutics’s therapeutic focus is primarily on sickle cell disease. In March,…