Bacteriophage Therapy for Orthopedic Implant-Associated Infections

Prospective, Single-Center, Single-Arm, Pre-Post Self-Controlled Study Evaluating the Efficacy and Safety of Bacteriophage Therapy in Orthopedic Implant-Associated Infections

A Prospective, Single-Center, Single-Arm Clinical Study with a Pre-Post Self-Controlled Design Evaluating the Efficacy and Safety of Bacteriophage Therapy for Refractory Orthopedic Implant-Associated Infections

Study Overview

• Status: Not yet recruiting
• Conditions: Implant Infection; Orthopedic
• Intervention / Treatment: Biological: bacteriophage preparation

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Zhao Ming Ye; Phone Number: 86-1360651549; Email: yezhaominghz@163.com
• Study Contact Backup: Name: Min Jun Yao; Email: yao_minjun@163.com

Study Locations

• China
  • Zhejiang
    • Hangzhou, Zhejiang, China, China 310000
      • The Second Affiliated Hospital of Zhejiang University School of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Known allergy or hypersensitivity to bacteriophages or any components of the bacteriophage preparation;
• Pregnant or breastfeeding women;
• Participation in another interventional clinical trial within the study period;
• Lack of feasible routes of administration other than intravenous injection;
• Patients deemed unsuitable for participation in this study by the investigator;
• Inability or unwillingness of the subject to comply with study procedures.

Exclusion Criteria:

• Withdrawal of informed consent by the participant at any time during the study;
• Occurrence of serious adverse events related to bacteriophage therapy that, in the investigator's judgment, necessitate discontinuation of treatment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Bacteriophage Therapy; To evaluate the infection control effect of bacteriophage therapy in treatment of refractory orthopedic implant-associated infections

Biological: bacteriophage preparation; After undergoing standard surgical debridement for orthopedic implant-associated infection. Bacteriophage preparation was administered primarily via postoperative indwelling catheter infusion. An appropriate volume of bacteriophage solution (adjusted according to joint cavity size and clinical assessment) was instilled directly through the catheter into the infected site, twice daily (bid) for 3 consecutive days per treatment cycle. During administration, strict aseptic procedures were maintained, and the distribution of the bacteriophage preparation within the joint cavity was ensured. Throughout the treatment period, patients were closely monitored for local and systemic adverse events related to bacteriophage therapy.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Bacterial eradication rate after bacteriophage therapy	The primary outcome of this study is the eradication of the target pathogen following bacteriophage treatment. Microbiological samples from the infection site will be collected before treatment and on days 1, 3, 5, and 7 after initiation of bacteriophage therapy for bacterial culture and identification. Bacterial eradication is defined as two consecutive negative cultures for the target pathogen after completion of bacteriophage therapy. If the target bacteria are still detected on day 3 or day 5, a reassessment will be performed to determine whether an additional cycle of bacteriophage therapy is required	Within 7 days after initiation of therapy

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical and inflammatory response improvement	The secondary outcome is the improvement of clinical symptoms and inflammatory indicators after bacteriophage therapy. Clinical improvement is defined by meeting the following criteria: Body temperature returns to normal, and local signs of infection (swelling, erythema, pain) are significantly alleviated or resolved, with satisfactory wound healing (no purulent discharge or exudation);; Blood routine parameters (white blood cell count, neutrophil ratio) and inflammatory markers, including C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), show a progressive decline and return to normal ranges;; Drainage from the infection site is significantly reduced or absent;; Imaging examinations (e.g., X-ray, CT, or MRI) demonstrate significant resolution of inflammatory lesions.	Within 1 month after treatment

Collaborators and Investigators

• Sponsor: Second Affiliated Hospital, School of Medicine, Zhejiang University

Study record dates

Study Major Dates

• Study Start (Estimated): April 5, 2026
• Primary Completion (Estimated): December 31, 2029
• Study Completion (Estimated): December 31, 2030

Study Registration Dates

• First Submitted: April 9, 2026
• First Submitted That Met QC Criteria: April 9, 2026
• First Posted (Actual): April 16, 2026

Study Record Updates

• Last Update Posted (Actual): April 16, 2026
• Last Update Submitted That Met QC Criteria: April 9, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Bacteriophage Therapy; Orthopedic Implant-Associated Infections
• Other Study ID Numbers: 2025-0401

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Due to policy constraints, it was not clear whether information could be shared.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No