The winners are James P. Allison and Tasuku Honjo for research to treat cancer using the body’s own immune system. The Nobel Prize officially was “for their discovery of cancer therapy by inhibition of negative immune regulation.” The Wall Street Journal reports:
The work of Drs. Allison and Honjo formed the backbone of new generations of blockbuster cancer immunotherapy drugs that are transforming treatment of some of the most intractable cancers. Though not all patients respond, these drugs can have a dramatic impact on advanced cases, most particularly melanoma—a form of skin cancer—and lung cancer.
Their work constitutes “a landmark in our fight against cancer,” the Swedish Academy—the body responsible for awarding the prize—said in announcing the awards.
A N.Y. Times article has a nice graphic explaining how the checkpoint inhibitors that Allison and Honjo discover worked. Dr. Allison identified a checkpoint called CTLA-4. Dr. Honjo found a different one, called PD-1.
A detailed summary is at the Nobel Prize website.