Tectitethya crypta (formerly known as Cryptotheca crypta) is a large, shallow-water sponge found in the Caribbean. It was first studied for medical purposes in the 1950s when few scientists or doctors thought to look for medicines in the ocean. But in the sponge, scientists isolated two chemicals—aptly named spongothymidine and spongouridine—which were used as models for the development of a number of anti-viral and anti-cancer drugs. These include the HIV drug AZT, a breakthrough in AIDS treatment in the late 1980s, anti-viral drugs to treat herpes, and an anti-leukemia drug. The latter was approved in 1969 and was the first marine-drug approved for cancer treatment.
Read more about medicines from the sea in this interview with Shirley Pomponi, medical sponge hunter.