Researchers at the University of Georgia have developed a new small molecule drug that may serve as a treatment against multi-drug resistant tuberculosis, a form of the disease that cannot be cured with conventional therapies. They describe their findings in a paper published recently in Bioorganic and Medicinal Chemistry Letters.

Nine million people contracted tuberculosis in 2013, and 1.5 million died from the disease, according to the World Health Organization. While standard anti-TB drugs can cure most people of Mycobacterium tuberculosis infection, improper use of antibiotics has led to new strains of the bacterium resistant to the two most powerful medications, isoniazid and rifampicin.

“Multi-drug resistant TB is spreading rapidly in many parts of the world,” said Vasu Nair, Georgia Research Alliance Eminent Scholar in Drug Discovery in the UGA College of Pharmacy and lead author of the paper. “There is a tremendous need for new therapies, and we think our laboratory has developed a strong candidate that disrupts fundamental steps in the bacterium’s reproduction process.”

Just like other living organisms, the genetic information contained in M. tuberculosis undergoes a complex process known as transcription in which the bacterial enzyme, DNA-dependent RNA polymerase, or RNAP, produces TB RNA. This molecule is involved in processes that produce critical bacterial proteins that the organism needs to survive.

The compound Nair and his colleagues developed works by binding to magnesium and specific amino acids found within the bacterium, interrupting the production of RNA.

“The compound we developed strongly inhibits the growth of the bacterium and renders it incapable of reproducing and spreading infection,” said Nair. “More importantly, the compound shows very low levels of cytotoxicity, which means that it is not harmful to the body.”