A new experimental antibiotic can handily knock off one of the world's most notoriously drug-resistant and deadly bacteria —in lab dishes and mice, at least. It does so with a never-before-seen method, cracking open an entirely new class of drugs that could yield more desperately needed new therapies for fighting drug-resistant infections.

The findings appeared this week in a pair of papers published in Nature, which lay out the extensive drug development work conducted by researchers at Harvard University and the Swiss-based pharmaceutical company Roche. //

In this case, the new drug—dubbed zosurabalpin—fights off the Gram-negative bacterium carbapenem-resistant Acinetobacter baumannii, aka CRAB. Though it may sound obscure, it's an opportunistic, invasive bacteria that often strikes hospitalized and critically ill patients, causing deadly infections worldwide. It is extensively drug-resistant, with ongoing emergence of pan-resistant strains around the world—in other words, strains that are resistant to every current antibiotic available. Mortality rates of invasive CRAB infections range from 40 to 60 percent. In 2017, the World Health Organization listed it as a priority 1: critical pathogen, for which new antibiotics are needed most urgently.

Zosurabalpin may just end up being that urgently needed drug, as Gugger and Hergenrother write in their commentary: "Given that zosurabalpin is already being tested in clinical trials, the future looks promising, with the possibility of a new antibiotic class being finally on the horizon for invasive CRAB infections."