Why Pfizer Stock Was Jumping Today, but Then Gave Up Its Gains

Shares of Pfizer (PFE -0.64%) jumped as much as 3.2% higher on Tuesday morning before giving up all of the gains and then some. The pharma stock was down by 0.6% as of 12:05 p.m. ET.These gyrations came after Pfizer announced its fourth-quarter and full-year results before the opening bell. The company reported Q4 revenue of $14.2 billion. Although this was a 41% year-over-year decline, it still topped Wall Street's consensus revenue estimate of$ 13.3 billion.Pfizer posted a Q4 loss of nearly $3.4 billion, ...