Tuberculosis (TB) is a disease that has existed among human populations for thousands of years. Caused by a bacterium, tuberculosis was perhaps at its deadliest during the 19th century, when it was popularly known as consumption. The disease continued to be a public health scourge into the early and mid-20th century. But increased knowledge of the disease’s contagious nature, greater efforts made to clean up squalid living conditions, and public health efforts to forbid spitting in public all helped to lessen the disease’s incidence.
What really tackled TB, however, was the development of antibiotics that could effectively combat the disease. The number of tuberculosis cases dropped precipitously, and at one point public health authorities thought that the disease might even be eliminated. Those hopes were dashed, however, as drug-resistant strains of TB began to occur.
Just as with other antibiotics, many TB patients failed to finish the full course of their antibiotic drugs, weakening but not eradicating the TB bacteria and allowing them to develop resistance to commonly-used antibiotics. That has given rise to antibiotic-resistant strains of TB that are becoming increasingly more common. While most cases of TB remain confined to the Third World, increased amounts of travel and immigration expose more and more people to TB every year, with TB once again becoming a public health issue in the Western world.
While new antibiotics have been developed that can treat drug-resistant TB, they are not 100% effective, which has spurred research into more effective remedies. Recently-published research findings have demonstrated that combining antibiotics with other drugs may be effective in treating cases of drug-resistant TB. Combining existing drugs is much easier than running experimental drugs through the testing and regulatory approval process.
Researchers used a commercially-available combination of the antibiotic ceftazidime with the enzyme inhibitor avibactam and found that it killed TB bacteria in the hollow fiber system model, an in vitro model used to evaluate tuberculosis treatments. Researchers were able to identify the ideal concentrations of the drugs to use to treat TB, which they hope could be used immediately in clinical use to treat drug-resistant TB. By identifying both the treatment and the means by which it worked, they also hope to develop a roadmap that will identify further treatments that can be used to take existing antibiotics and enlist them in the fight against drug-resistant TB.