A research team in Zurich, Switzerland has presented results from an in vitro study showing that photodisinfection achieved >99.99% eradication (4-7 log10 kill) of the key pathogens in biofilms associated with implantable joint infections, with no reported regrowth. These results were presented at the recent Swiss Society for Microbiology (SSM) Annual Congress 2022 in Lausanne, Switzerland.
Periprosthetic joint infections (PJIs) are typically extremely hard to treat,1 but this new research finds that photodisinfection may be an exciting new treatment approach. The research team, lead by Dr. Yvonne Achermann, is planning further clinical research on the safety and efficacy of the PJI treatment.
PJIs are most commonly caused by the bacteria Staphylococcus aureus (S. aureus).2 Patients undergoing major surgeries like hip or knee replacements face the risk of life-threatening infections, with the majority of these related to the patients’ own microflora. In the US alone, the annual cost of treating PJIs is estimated at $1.62 billion.3
Lead author, Julia Prinz, commented: “PJIs are difficult to treat due to biofilm formation on implant surfaces. These infections often require removal or exchange of prostheses and long-duration antibiotic treatment. We found that photodisinfection effectively eradicated important pathogens involved in PJI – whether in planktonic form or biofilms grown on commonly used arthroplasty materials – and without harming the prosthetic materials.”
Photodisinfection, also known as antimicrobial photodynamic therapy (aPDT), is a broad-spectrum antimicrobial treatment which uses non-thermal light to activate a photosensitive agent. In a few minutes, this light-based therapy destroys pathogens through an oxidative burst without harming the implant or human tissue. Importantly, photodisinfection is effective against drug-resistant pathogens and does not cause resistance-formation, both distinct advantages over antibiotics.
The photodisinfection technology used in the study was provided by Canadian life sciences company Ondine Biomedical, who recently announced results from its US Phase 2 trial showing that nasal photodisinfection eliminated or significantly decreased nasal S. aureus in 92% of pre-surgical patients.4
The poster entitled “In vitro methylene blue based antimicrobial photodynamic therapy for effective biofilm eradication in periprosthetic joint infection” was presented by Julia Prinz at the SSM Annual Congress 2022 in Lausanne, Switzerland (all authors: Julia Prinz, Marianne Wink, Sonja Neuhaus, Markus C. Grob, Heinrich Walt, Philipp P. Bosshard, Yvonne Achermann).
For further information, please visit: www.ondinebio.com
References
2. Causes and Diagnoses of Prosthetic Joint Infections. Northwestern Medicine website.
3. Prosthetic Joint Infections and Cost Analysis?
4. Ondine Biomedical reports successful US phase 2 trial data
