Antibiotic-loaded microneedles show promise against MRSA

Microneedle patches have shown promise in the delivery of antibiotics locally to the skin, raising the prospects of being able to treat infections without subjecting patients to systemic therapy.

Writing in the journal Advanced Materials Technologies, researchers at Sweden’s Karolinska Institutet describe the use of microneedles loaded with the antibiotic vancomycin to treat methicillin‐resistant Staphylococcus aureus (MRSA) skin infections in preclinical tests. The approach offers several potential benefits over the systemic administration of antibiotics.    

Local administration of vancomycin could spare patients from the side effects associated with intravenous delivery of the antibiotic. When given intravenously, a high dose must be used to ensure enough antibiotic gets to the targeted bacteria, but concentrations in the skin are still fairly low. The injection of vancomycin to treat skin infections therefore raises the risk of drug resistance. 

Working with skin from piglets and humans, the Karolinska researchers showed vancomycin‐loaded microneedle arrays can overcome the natural limitations of the antibiotic in topical applications. The antibiotic was delivered into the skin and significantly reduced the population of MRSA bacteria. 

The early success has encouraged the researchers to further develop the technology, including by evaluating the performance of the vancomycin‐loaded microneedles in animal models of MRSA infection such as humanized mouse models. The studies will build the case for potentially trying to translate the technology to the clinic. 

"If this drug delivery device reaches the clinics, it has the capacity to transform the way skin infections from potentially lethal bacteria are treated with drastic improvements in the quality of life of patients," Karolinska’s Georgios Sotiriou, Ph.D., the last author of the study, said in a statement.

The researchers used a water‐soluble polymer to facilitate effective drug release in the skin, as well as a water‐insoluble polymer layer designed to facilitate precise drug dosage formulation.