Complex sentence: When Upjohn received permission from the FDA to test the new drug as medicine for hypertension they approached Charles A. Chidsey MD, Associate Professor of Medicine at the University of Colorado School of Medicine., who conducted two studies, the second study showing unexpected hair growth.
Split into simpler sentences: When Upjohn received permission from the FDA to test the new drug as medicine for hypertension they approached Charles A. Chidsey MD, Associate Professor of Medicine at the University of Colorado School of Medicine. He conducted two studies, the second study showing unexpected hair growth.