Nobel Prize in medicine honors pioneering research that helps fight disease The 2019 Nobel Prize for medicine has been jointly awarded to three scientists for their pioneering research into how human cells respond to changing oxygen levels. The Nobel committee said the discoveries of Sir Peter Ratcliffe, William Kaelin Jr. and Gregg Semenza have paved the way for promising new strategies to fight anemia, cancer and many other diseases. Anne-Marie Green and Vladimir Duthiers have more.