Scientists have discovered an entirely new class of antibiotic that appears to kill one of three bacteria considered to pose the greatest threat to human health because of their extensive drug-resistance.

Zosurabalpin defeated highly drug-resistant strains of Carbapenem-resistant Acinetobacter baumannii (Crab) in mouse models of pneumonia and sepsis, and was being tested in human trials.

Crab is classified as a priority 1 critical pathogen by the World Health Organization, alongside two other drug-resistant forms of bacteria – Pseudomonas aeruginosa and Enterobacteriaceae.
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No new antibiotic for Gram-negative bacteria have been approved in more than 50 years.

https://www.theguardian.com/science/2024/jan/03/scientists-new-class-antibiotic-kill-drug-resistant-bacteria