Alchemia soars: looks to break down the walls of antibiotic resistance

Shares in Brisbane drug-developer Alchemia (ASX:ACL) rose 50 per cent to $0.80 today, on the back of news that it would be targeting antibiotic-resistant "superbugs" with a novel class of synthetic molecules that disrupt cell-wall synthesis in bacteria.

Microbiologists at the University of Leeds' Antimicrobial Research Centre in the UK have shown that the Alchemia compounds inhibit transglycosylase enzymes required for cell-wall synthesis.

Describing the compounds as a potential breakthrough for combating hospital-acquired infections, Alchemia CEO Dr Tracie Ramsdale said the UK tests confirmed that the compounds are highly active against multi-drug resistant bacteria.

Ramsdale said very few novel antibacterial compounds in the international pipeline for treating multi-drug resistant, gram-positive bacteria.

Not only were there very few antibiotics in development, bacterial resistance to existing drugs of last resort is increasing rapidly, creating a serious health issue for the international healthcare community.

Ramsdale said Alchemia's new compounds, because they have a mode of action not exploited by any previous antibiotic, are "potentially the most extraordinary scientific development in several decades" in combating multi-drug resistant bacteria."

Ransdale said, that, for this reason bacteria were likely to take much longer to develop resistance to the Alchemia molecules. Because of their central role in replication, transglycosase genes are strongly conserved in gram-positive bacteria.

Gram-positive bacteria have sticky cell walls, built from proteins festooned with sugar molecules. The transglycosylase (TG) enzymes perform the protein-glycosylation reactions.

Sugars are carbohydrates, and Ramsdale said Alchemia's expertise in synthesising carbohydrate-based molecules was "a good fit" for disrupting bacterial carbohydrate synthesis - over the years, researchers had tried and failed to develop drugs to disrupt cell-wall synthesis.

The new TG-disrupting molecules have displayed significant activity against including clinical isolates of methicillin-resistant strains of Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE).

"Effectively, these test results verify that our compounds are suitable candidates for treating hospital-acquired infections," Ramsdale said.

"In the US alone, the healthcare bill associated with treating hospital-acquired infections exceeds $US4.5 billion each year."

Alchemia will immediately begin to study the efficacy of the compounds in animal models of resistant bacterial infections, and expects to have results by year's end. Ramsdale said if the efficacy tests are positive, it will seek a suitable partner to take them into human clinical trials.

The company will present detailed results of the Leeds University study at the US Biotechnology Conference in New York on October 27.