Gertrude Elion was awarded the 1988 Nobel Prize in Physiology or Medicine. Unable to obtain a graduate research position, she worked as a lab assistant and a high school teacher. Later, she worked as an assistant to George H. Hitchings at the Burroughs-Wellcome pharmaceutical company (now GlaxoSmithKline). She never obtained a formal Ph.D., but was later awarded an honorary Ph.D from Polytechnic University of New York where she attended but did not graduate. Elion and Hitchings used the differences in biochemistry between normal human cells and pathogens to design drugs that could kill or inhibit the reproduction of particular pathogens without harming the host cells.