Infection Control Today (11.26.12)
Aids Weekly Plus
Researchers at the University of British Columbia’s (UBC) Department of Microbiology and Immunology associated with UBC’s Centre for Tuberculosis Research and the Neglected Global Diseases Initiative found that a class of drugs used in developing countries to treat parasitic diseases has potential for use in treating TB. These drugs—in the avermectin drug family—have been considered ineffective against bacterial diseases, but during in vitro tests, they killed the bacteria that cause TB, including the drug-resistant strains.
Santiago Ramón-García, a co-author of the study, stated that the drugs are cheap and routinely manufactured by drug companies, and since some of them are already approved for human use, the transition from laboratory to clinical use could be much quicker than usual. He noted that the drug concentrations effective in vitro indicate that drug members of this family might be very valuable in treating multi-drug-resistant TB, which at present has a very low probability of being cured. Additional research is necessary to determine the drugs’ clinical application for treating TB. The researchers are working with animal models to find the effective dosage levels and regimens. They will also study if these drugs can be combined with others to create more effective therapies.
At present, three members of the family of avermectins—ivermectin, selamectin, and moxidectin—are bactericidal against mycobacterial species including multi-and extensively drug-resistant Mycobacterium tuberculosis. Ivermectin is approved for clinical use in humans, and selamectin and moxidectin are approved for veterinary use. Moxidectin recently passed clinical trials for human use.
The Canadian Institute of Health Research, the British Columbia Lung Association, Grand Challenges Canada—Stars in Global Health, and the National Institutes of Health funded the research.
The study, “Anthelmintic avermectins kill M. tuberculosis, including multidrug resistant clinical strains,” was published ahead of print in the journal Antimicrobial Agents and Chemotherapy (2012; doi:10.1128/AAC.01696-12).