Procedures such as knee and hip replacements can expose patients to potential bacterial infections, and bone cements are one way physicians can lower the risk. These materials anchor the artificial joint in place and, if loaded with antibiotics, can protect against harmful bacteria at the site. But the rise of drug-resistant bacteria calls for new approaches to these types of problems, and a potent new form of bone cement is poised to take up the fight.
“Currently, the Food and Drug Administration (FDA) has only approved of bone cements loaded with antibiotics not originally developed for bone tissue,” said study author Hae Lin Jang, from Brigham and Women’s Hospital. “In addition to not being bone tissue-specific, resistance has emerged against these antibiotics. We must create a new generation of antibiotics that are optimized to meet this emerging need.”
In search of new and improved antibiotic-loaded bone cements, the scientists screened a library of antibiotics for activity against bacterial targets shown to have resistance against multiple drugs. This led them to a dual-action antibiotic called VCD-077, which was loaded into a bone cement made from polymethylmethacrylate (PMMA), the FDA-approved gold-standard.
The novel antibiotic-loaded bone cement was put to the test in experiments on cells and rat models, with its performance compared to a regular, clinically-used PMMA bone cement. The addition of the antibiotic was found to have no effect on the stability of the cement, and was able to be released from the material in the desired fashion. It also demonstrated high efficacy against a broad range of drug-resistant bacteria and hampered the development of bacterial resistance.
Most promisingly, the novel bone cement showed greater efficacy against Staphylococcal bone infections in the rat models than all antibiotic-loaded bone cements currently in use.
There is a lot to play out before the team deploys its novel bone cement against bacterial infections in clinics, with toxicity levels a question that remains unanswered. But using bone cement as a targeted drug delivery method generally has advantages over systemic antibiotic treatment that requires large doses and promotes drug resistance at the same time. So with further work, the technology may play an important role in both promoting patient recovery and curtailing the rise of antibiotic resistance.
The research was published in the journal Nature Biomedical Engineering.
Source: Brigham and Women’s Hospital
