NEW YORK — A patient enrolled in a long-term study of Pfizer’s hemophilia drug Hympavzi has died after experiencing serious side effects, the company said. Pfizer confirmed the patient died on Dec.NEW YORK — A patient enrolled in a long-term study of Pfizer’s hemophilia drug Hympavzi has died after experiencing serious side effects, the company said. Pfizer confirmed the patient died on Dec.


