Researchers have monkeyed around with one of the stronger antibiotics available for use on humans, resulting in a drug that fights pathogens in three different ways and is thousands of times more powerful than its current form. However, it still hasn’t been tested on humans, meaning it’s a long way from reaching pharmacy shelves.
Vancomycin is a very powerful antibiotic that’s been in use for about 60 years, but it’s long been considered a drug of “last resort” for two reasons. First, it can be incredibly harsh for the patient. From personal experience: I had to be treated with vanco after surgery several years back, and not only did it require intravenous antihistamines to make the drug tolerable, nurses had to move my IV to a different location every day because the injection sites would become damaged.
Second, just like other antibiotics, frequent use of vancomycin will only encourage the development of drug-resistant bacteria. There are already vanco-resistant strains of pathogens like Enterococcus and Streptococcus, so physicians need to deploy the drug judiciously in order to avoid rendering it useless down the road.
Scientists from the Scripps Research Institute have been tinkering with vancomycin for years, attempting to craft a better, more efficient version of the antibiotic. In a report published this week in the Proceedings of the National Academy of Sciences, they detail the results of said tinkering: a vanco that works in three different ways to kill bacteria and which appears to be less likely to promote resistance.
Vancomycin’s primary way of killing bacteria is to block them from building cell walls. Vanco-resistant pathogens have figured out a way to keep building that wall, swapping out the original protein with a different one. The Scripps team says their new vancomycin prevents both proteins.
Additional tweak to the drug helps to halt the entire process of cell wall construction, while the final tine of the trident ruptures the cell membrane, leading to the bacteria’s death.
Most importantly, these three power-ups to vancomycin appear to work independently of each other, so the bacteria would need to develop resistance to all three attacks to render vanco pointless.
While the development of a very powerful, ultra-efficient vancomycin is hopeful, the drug has not been tested on animals for safety and effectiveness. The researchers say they currently have no indication that this newer vanco would be overly toxic to mammals, but that will still need to be tested.
It’s been decades since the last new class of antibiotics, and as common infections become more difficult to treat with traditional antimicrobials, hospitals have been increasingly turning to drugs that treat antibiotic-resistant pathogens.
Last year, a rare gene plasmid — which can move between cells of different types and confer resistance to colistin, another last-resort drug, on a variety of bacteria — was discovered in a human patient in the U.S.. Dr. Tom Frieden, then-Director of the Centers for Disease Control and Prevention, cautioned that “The medicine cabinet is empty for some patients.”