William Campbell

Drew University

William Campbell is an Irish-American biologist and parasitologist who served for many years at Merck Research Laboratories before joining Drew University in Madison, New Jersey. He shared the 2015 Nobel Prize in Physiology or Medicine with Satoshi Omura for the discovery of a novel therapy against roundworm parasites, and the other half was shared with Youyou Tu for her work on malaria. Campbell and Omura discovered avermectin, a class of macrocyclic lactone compounds derived from the soil bacterium Streptomyces avermitilis. Campbell's contribution was identifying the extraordinary antiparasitic activity of avermectin against a broad spectrum of nematode and arthropod parasites, and guiding its development into ivermectin—a semisynthetic derivative with even greater efficacy and safety. Ivermectin has had an enormous impact on global health, particularly in Africa and Latin America, where it is used in mass drug administration programs to control onchocerciasis (river blindness) and lymphatic filariasis, diseases that cause blindness and severe disability in hundreds of millions of people. The Mectizan Donation Program, initiated by Merck, has distributed ivermectin free of charge to over 300 million people annually. Ivermectin has also transformed veterinary medicine as a treatment for parasites in livestock and companion animals. Campbell received recognition through honorary degrees from institutions including Trinity College Dublin. His work represents a model for pharmaceutical discovery applied to neglected tropical diseases.