Phage Therapy for Orthopaedic Infections: The First Three Cases from the United Kingdom.

Background: Bacteriophages (phages) are viruses that infect and kill bacteria. The antimicrobial resistance crisis has driven renewed interest in phage therapy, including the use of phages to treat chronic orthopaedic infections. Methods: Here, we present the results of the first three orthopaedic patients treated with phage therapy in the United Kingdom. Results: The first patient was treated in May 2023 and received phages active against Staphylococcus aureus. At nine months follow-up, the patient's wound remained healed, the C-reactive protein normal and the patient was walking independently. The second patient received phages active against Klebsiella pneumoniae and S. aureus; the infection remained unresolved. The third patient received phages active against Staphylococcus epidermidis; at six months follow-up, the patient was free of infection. Endotoxin was considered at least partially responsible for mild self-limiting adverse effects in two cases. Conclusions: These promising results hint at the potential for phage therapy to transform the care of chronic orthopaedic infections.