ACTIVE2

Inclusion Criteria: * Males or females ≥18 years of age * Recurrent PJI of the knee or hip * Female patients of childbearing potential who agree to use contraception. * Confirmed phage match * No anticipated need for long-term antibiotics Exclusion Criteria: * Soft tissue defect requiring reconstruction * Hardware misalignment * Additional orthopedic hardware in connection with the infected prosthesis * Active infection (other than PJI) requiring long term IV antibiotics * Unable to tolerate SAT * Septic shock or hemodynamic instability * Stage 4 or greater chronic kidney disease * Liver disease * Decompensated heart failure * Positive drug screen * Receiving chemotherapy * Immunocompromised * Treatment with antiviral medication within 2 weeks prior to randomization * Currently participating in another clinical trial * Known phage allergy * Pregnant/ breast feeding * Lack of capacity to consent