William C. Campbell (scientist)

William Cecil Campbell (June 28, 1930 – July 17, 2023) was an Irish-born American parasitologist and biologist known for his work in discovering a novel therapy against infections caused by roundworms. He shared the 2015 Nobel Prize in Physiology or Medicine with Satoshi Ōmura for their discoveries concerning a new therapy against infections caused by roundworm parasites. Specifically, Campbell and Ōmura's work led to the development of ivermectin, a drug that has proven extraordinarily successful in treating onchocerciasis (river blindness) and lymphatic filariasis, among other parasitic diseases.

Campbell received his BA in Zoology from Trinity College, Dublin in 1952 and his PhD in Veterinary Parasitology from the University of Wisconsin–Madison in 1957. He spent most of his career at Merck & Co., where he became a senior scientist. He retired in 1990 and subsequently became a research fellow at Drew University in Madison, New Jersey.

His research focused on identifying and developing antiparasitic drugs for both animals and humans. His collaboration with Satoshi Ōmura led to the isolation of avermectin from soil microorganisms, which was then chemically modified by Campbell and his team to create ivermectin. Ivermectin has revolutionized the treatment of parasitic diseases, especially in developing countries, and has been instrumental in significantly reducing the incidence of onchocerciasis and lymphatic filariasis globally. His contributions have had a profound impact on global health and have earned him numerous accolades, culminating in the Nobel Prize.