Tasuku Honjo

Tasuku Honjo discovered the PD-1 protein in 1992 and subsequently demonstrated that PD-1 functions as a key immune checkpoint whose blockade can stimulate anti-tumor immunity. His discovery, made at Kyoto University, led directly to the development of nivolumab and pembrolizumab — the anti-PD-1 antibodies that have transformed treatment across numerous cancer types. He shared the 2018 Nobel Prize in Physiology or Medicine with James Allison for these complementary discoveries that established modern cancer immunotherapy.