In 2015, he was awarded the Nobel Prize in Physiology or Medicine jointly with William C. Campbell for their role in the discovery of avermectins and ivermectin, [1] the world's first endectocide and a safe and highly effective microfilaricide.

[2] It is believed that the large molecular size of ivermectin prevents it from crossing the blood/aqueous humour barrier, and renders the drug an important treatment of helminthically-derived blindness.

After graduating from the University of Yamanashi in 1958, he was appointed to science teacher at Tokyo Metropolitan Sumida Tech High School.

[5] In 1971 while he was a visiting professor at Wesleyan University,[4] he consulted the chairman of the American Chemical Society, Max Tishler, at an international conference.

He was awarded the 2015 Nobel Prize in Physiology or Medicine jointly with William C. Campbell for discoveries concerning a novel therapy against infections caused by roundworm parasites.

[2] Campbell later acquired these bacteria and developed the derived drug ivermectin that was first commercialised for veterinary use in 1981 later put to human use against Onchocerciasis in 1987–88 with the name Mectizan,[2] and is today used against river blindness, lymphatic filariasis, scabies, other parasitic infections.