Discovery of Sulfonamide Antibacterial Drugs

German pathologist and bacteriologist Gerhard Domagk, working with chemist Josef Klarer at the Bayer laboratories, discovered in the early 1930s that a red azo dye called Prontosil, first tested in 1932, could cure mice of otherwise fatal streptococcal infections, becoming the first medicine ever shown to treat a range of bacterial infections effectively. French researchers at the Pasteur Institute soon determined that Prontosil worked only after the body broke it down into a simpler compound, sulfanilamide, the active antibacterial agent; because sulfanilamide itself had been synthesized decades earlier and its patent had already expired, the discovery could not be monopolized and touched off rapid development of an entire class of sulfonamide, or sulfa, drugs by laboratories worldwide. Domagk received the 1939 Nobel Prize in Physiology or Medicine for the discovery, though the government of Germany at the time forced him to decline it; sulfonamides became the first widely effective synthetic antibacterial drugs, preceding penicillin's clinical introduction by several years.