George Rainer Siber (born September 7, 1944) is a medical researcher and vaccine expert with 44 years of experience in developing numerous vaccines, therapeutic antibodies, and diagnostic agents for infectious diseases.
Siber is a former Harvard professor, current Adjunct Professor at Johns Hopkins University and Professor at the University of Massachusetts Medical School, former Executive Vice President and Chief Science Officer of Wyeth, and Advisory Committee member of the World Health Organization, US National Institutes of Health, Gates Foundation, and the National Institute of Allergy and Infectious Diseases.