New class of antibiotics developed to fight drug-resistant bacteria

New Delhi: Researchers have developed a new class of antibiotics that may be effective against a bacterium called Carbapenem-resistant Acinetobacter baumannii (CRAB), known to be resistant to existing drugs.

The scientists said that the antibiotic candidate, called zosurabalpin, was found effective in the lab and in mouse models.

CRAB is a species of Gram-negative bacteria, known to be difficult to kill because their outer membrane contains contains lipopolysaccharide (LPS), which renders the bacteria protection against several antibiotics.

The team of researchers, including those from Roche Pharma Research and Early Development, Roche Innovation Center Basel, Switzerland, and Harvard University, US, explained that the new drug worked by preventing the LPS from reaching CRAB's outer membrane by arresting the transport compound enabling the movement of the LPS.

This suggested the drug's capacity to circumvent existing resistance mechanisms, they said.

The researchers said that zosurabalpin showed "promise in tackling the highly resistant pathogen CRAB", and that ongoing human trials will help develop this drug further for clinical use.

However, the team also acknowledged that "the potential for the emergence of resistance to this new compound requires further investigation under clinically relevant conditions." They have published their findings in the journal Nature.

Antibiotic resistance, which happens when disease-causing germs evolve and become shielded from the effects of antibiotic drugs, has been widely acknowledged as an urgent public health threat in recent decades.

In an accompanying paper in the same journal, some researchers from this team examine the mechanisms through which this new class of antibiotics works. They showed that they trap the LPS transport compound, disabling it from moving LPS, thereby resulting in the cell's death.

The findings of these studies also suggest that a specific conformation of the LPS transporter could be an effective therapeutic target for developing compounds directed against other Gram-negative bacteria, the researchers said.