Experts create ‘living medicine’ to treat antibiotic-resistant bacteria

Researchers have created the first “living medicine” to treat bacteria that is resistant to antibiotics and grows on the surface of medical implants.

For the experimental treatment, experts genetically removed the bacteria’s ability to cause disease and forced it to attack harmful microbes instead.

Researchers at the Centre for Genomic Regulation (CRG) and Pulmobiotics SL in Barcelona said their findings are an important first step in the development of treatments for infections on medical implants such as catheters, pacemakers and prosthetic joints.

These bacteria can be highly resistant to antibiotics and account for a large proportion of hospital-acquired infections.

The study, published in the journal Molecular Systems Biology and supported by funding from bodies including the European Research Council, tested the new medicine on infected catheters, including in mice.

It suggests that injecting the therapy under the skin of mice treated infections in 82% of the animals.

The new treatment specifically targets biofilms, which are colonies of bacterial cells that stick together on a surface.

The surfaces of medical implants are ideal growing conditions for biofilms, which prevent antibiotics or the human immune system from being able to attack the bacteria embedded within.

In the treatment, a common species of bacteria was modified to make it produce two different enzymes that dissolve biofilms and attack the cell walls of the bacteria.

The researchers also modified the bacteria so that it secreted anti-microbial enzymes more effectively.

The team now hope to use the modified bacteria to treat biofilms on breathing tubes, as a first step.

Maria Lluch, co-corresponding author of the study and chief science officer of Pulmobiotics, said: “Our next challenge is to address high-scale production and manufacturing, and we expect to start clinical trials in 2023.”

Co-author of the study, research professor Luis Serrano, said: “Bacteria are ideal vehicles for ‘living medicine’ because they can carry any given therapeutic protein to treat the source of a disease.

“One of the great benefits of the technology is that, once they reach their destination, bacterial vectors offer continuous and localised production of the therapeutic molecule.

“Like any vehicle, our bacteria can be modified with different payloads that target different diseases, with potentially more applications in the future.”