Pfizer has a long tradition of incorporating the names of the Pharmaceutical companies it has acquired.
The letter E and R was incorporated from WarnER-LambERt = (pfizER) Twice actually!
The letter P, I, and R was incorporated from Pharmacia = (PfIzeR)
The letter E and R was incorporated from Searle = (pfizER)
The letter P was incorporated from Upjohn = (Pfizer)
The letter E was incorporated from Wyeth = (pfizEr)
The letter I was incorporated from King = (PfIzer)
Therefore, due to the generous tradition of adding the names of its acquisitions, it is with absolute certainty that Pfizer will ignominiously incorporate the Z and E from AstraZeneca = (pfiZEr)