Research by a collaborative group of scientists from UC San Diego School
of Medicine, UC San Francisco and Wake Forest School of Medicine has
led to identification of an existing drug that is effective against Entamoeba histolytica. Using a high-throughput screen for drugs developed by the research team,
they discovered that auranofin (see structure) a drug approved by the US Food and
Drug Administration 25 years ago for rheumatoid arthritis -- is very
effective in targeting an enzyme that protects amebae from oxygen attack
(thus enhancing sensitivity of the amebae to reactive oxygen-mediated
killing).
Entamoeba histolytica is a protozoan intestinal parasite
that causes human amebiasis, the world's fourth leading cause of death
from protozoan parasites. It is listed by the National Institutes of
Health as a category B priority biodefense pathogen. Current treatment
relies on metronidazole, which has adverse effects, and potential
resistance to the drug is an increasing concern.
