E. coli Bacteria. Image/National Institute of Allergy and Infectious Diseases, National Institutes of Health

Scientists have developed a new class of antibiotics that could kill an anti-biotic-resistant (AMR) bacteria classified as a major threat by the World Health Organisation.

The drug Zosurabalpin is found to be effective against CRAB (carbapenem-resistant Acinetobacter baumannii)-induced pneumonia and sepsis in mouse models.

Crab has been classified as a priority 1 critical pathogen by the World Health Organisation. It is associated with high mortality rate due to high levels of resistance to antibiotics. It can cause lung, urinary tract, and blood infections.

The researchers from Harvard University and the Swiss healthcare company Hoffmann-La Roche, during their study, found that the drug was effective against more than 100 CRAB clinical samples.

The findings of the ground-breaking discovery have been published in the journal Nature. The antibiotic is currently undergoing human trials.

Zosurabalpin works by stopping lipopolysaccharide (LPS) transport to the outer membrane of the bacteria. These molecules then pile up inside the bacteria, and it dies eventually. "LPS allows bacteria to live in harsh environments, and it also allows them to evade attack by our immune system," said Dr. Michael Lobritz of Roche Pharma Research and Early Development.

"This is the first time we've found anything that operates in this way, so it is unique in its chemical makeup and mechanism of action," added Lobritz.

The big picture:

Antimicrobial resistance is a major public health concern around the world. AMR occurs when bacteria adapt and antibiotics no longer work for people who need them to treat infections.

Although these bacteria are present in the intestinal flora of humans and animals, they can cause devastating infections in people with weakened immune systems. The bacteria that pose the biggest threat are Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacteriaceae, according to the WHO.

Some lethal bacteria are resistant to all medically approved antibiotics. At least 700,000 people die every year due to these fatal superbugs, and if timely action is not taken, the number of deaths could rise to 10 million by 2050.

In 2016, a review commissioned by the UK government warned that antibiotic-resistant superbugs would kill one person every three seconds and cause trillions of dollars of economic damage by 2050 if left unchecked.

The review estimated that around a third of the 10 million deaths arising from antimicrobial resistance (AMR) in 2050 would come from drug-resistant E. coli. It said that AMR could kill up to 10 million people each year by 2050 at a cumulative cost of $100 trillion (£69 trillion, €89 trillion) to the global economy.

The experts believe that it is essential to reduce drug use in farming if we wish to curtail the number of deaths reported every year.