Medicinal chemist, integral part in development of cimetidine. Listed as inventor or co-inventor of 160+ US patents as well as authored & co-authored over 260 scientific papers. Was inducted into the National Inventor's HOF for his work on cimetidine

Co-winner 2015 Nobel Medicine Prize/cited for discovering avermectin, derivatives of which helped lower incidence of river blindness & lymphatic filariasis 2 diseases caused by parasitic worms that affect millions of African & Asian people