The continuing rise of antibiotic-resistant bacteria, also known as superbugs, is a growing concern, with some experts predicting they could kill millions per year by 2050. These bugs are evolving to evade our very best drugs, but knowing which ones are likely to do so ahead of time could give us a chance to fine-tune our treatments. Scientists have made a significant breakthrough by pinpointing signs of “pre-resistance” in bacteria for the first time, which they say could allow for better targeted therapies that nip superbugs in the bud.

The international team of scientists behind the study was working towards advanced treatments for tuberculosis (TB), which killed 1.5 million people in 2020, making it the second leading cause among infectious diseases, behind COVID-19. TB bacteria can develop resistance to drugs when the medicines used to tackle the curable disease are misused or mismanaged, such as missed dosages or premature ending of the treatment regime.

Treating multidrug-resistant TB is an expensive and lengthy process, and can cost upwards of half a million US dollars to tackle its most extreme forms. The authors of this new study set out to better understand how these strains develop, and ways in which they might be better treated or, ideally, prevented from taking shape.

To do so, the team analyzed the genomes of more than 3,000 different TB samples, using them to construct a bacterial “family tree.” With the help of computer analysis, the team then identified the ancestral genetic code of bacteria that developed drug resistance down the track, allowing them to predict which lineages, or “branches” of the tree, were likely to become drug-resistant.

“We’re running out of options in antibiotics and the options we have are often toxic – we have to get smarter at using what we have to prevent drug resistance,” says study leader Dr Louis Grandjean. “This is the first example of showing that we can get ahead of drug resistance. That will allow us in the future to use the pathogen genome to select the best treatments.”

The team considers this the first evidence of what they call “pre-resistance,” or identification of signs that bacteria or a virus has an increased risk of developing drug resistance in the future. They say this approach can potentially be applied to other infectious diseases, and could lead to therapies that are tailored to the DNA of specific pathogens in order to prevent drug resistance from developing.

“We hope this discovery could provide a way of treating difficult conditions in the future by targeting specific pathogen genomes that are most likely to become drug resistant in the future,” says Arturo Torres Ortiz from University College London, first author of the paper.

The research was published in the journal Nature Communications.

Source: University College London