Pharma sector down after Trump tweet

One sector down is pharma, this after Trump took to twitter to bludgeon them, tweeting "Pfizer & others should be ashamed that they have raised drug prices for no reason. They are merely taking advantage of the poor & others unable to defend themselves, while at the same time giving bargain basement prices to other countries in Europe & elsewhere. We will respond!" Pfizer shares getting hit here, is he back on the big pharma warpath?