CBD has been shown to kill the bacteria responsible for gonorrhoea, meningitis and legionnaires disease in a discovery which could pave the way for the first new class of antibiotics for resistant bacteria in a generation, according to researchers from the University of Queensland and Botanix Pharmaceuticals.
UQ Institute for Molecular Bioscience Associate Professor Mark Blaskovich said CBD can penetrate and kill a wide range of bacteria including Neisseria gonorrhoeae, which causes gonorrhoea.
“This is the first time CBD has been shown to kill some types of Gram-negative bacteria. These bacteria have an extra outer membrane, an additional line of defence that makes it harder for antibiotics to penetrate,” he added.
Gonorrhoea is the second most common sexually-transmitted infection in Australia and there is no longer a single reliable antibiotic to treat it because the bacteria has developed resistance.
The study, published in Communications Biology, also showed CBD was effective against a much larger number of Gram-positive bacteria than previously thought, including antibiotic-resistant pathogens such as MRSA or ‘golden staph’.
Dr Blaskovich said CBD was particularly good at breaking down biofilms, the slimy build-up of bacteria such as dental plaque on the surface of teeth, which help bacteria like MRSA survive antibiotic treatments.
The team at the Centre for Superbug Solutions mimicked a two-week patient treatment in laboratory models to see how fast the bacteria mutated to try to outwit CBD’s killing power.
“Cannabidiol showed a low tendency to cause resistance in bacteria even when we sped up potential development by increasing concentrations of the antibiotic during ‘treatment’.
“We think cannabidiol kills bacteria by bursting their outer cell membranes, but we don’t know yet exactly how it does that, and need to do further research.”
The team also discovered chemical analogs – created by slightly changing CBD’s molecular structure – were also active against the bacteria.
“This is particularly exciting because there have been no new molecular classes of antibiotics for Gram-negative infections discovered and approved since the 1960s, and we can now consider designing new analogs of CBD within improved properties,” added Dr Blaskovich.
President and executive chairman of Botanix Vince Ippolito said the research showed great potential for the development of effective treatments to fight the growing global threat of antibiotic resistance.
He added: “Our company is now primed to commercialise viable antimicrobial treatments which we hope will reach more patients in the near future. This is a major breakthrough that the world needs now.”
Botanix contributed formulation expertise to the research which led to the discovery that the way in which CBD is delivered makes a big difference to its effectiveness in killing bacteria.
The collaboration has enabled Botanix to progress a topical CBD formulation into clinical trials for decolonisation of MRSA before surgery.
Dr Blaskovich said: “Those Phase 2a clinical results are expected early this year and we hope that this will pave the way forward for treatments for gonorrhoea, meningitis and legionnaires disease.
“Now we have established that cannabidiol is effective against these Gram-negative bacteria, we are looking at its mode of action, improving its activity and finding other similar molecules to open up the way for a new class of antibiotics,” he added.