Sola2 AMF Knee System Added to Surgery and Antibiotics in Adults With Knee Implant Infection

Official title

Acute Management of PJI With Local Implant Retention and Antibiotics Using the Sola2 AMF Knee System: A Multicenter Double-blind Clinical Trial.

Overview

The goal of this clinical trial is to learn whether the Sola2 AMF Knee System, when added to surgery and antibiotic treatment, can safely improve outcomes, knee function, and quality of life in adults with knee implant infection. The main questions this study aims to answer are: 1. Whether adding the Sola2 AMF Knee System improves knee function and quality of life at 6 months. 2. Whether adding the Sola2 AMF Knee System to surgery and antibiotic treatment affects the need for additional infection-related surgery. 3. Whether the Sola2 AMF Knee System can be used safely, based on device-related adverse events through 12 months. This study has two stages. In Stage 1, participants will be enrolled into sequential sentinel groups at increasing AMF temperature levels. All sentinel participants will receive active Sola2 AMF treatment. A safety review will occur after each sentinel group before proceeding to the next group. In Stage 2, researchers will compare participants who receive active Sola2 AMF treatment to participants who receive sham AMF treatment. All participants will receive surgery called debridement, antibiotics, and implant retention (DAIR), and antibiotic treatment for knee implant infection. Participants will: * Have DAIR surgery for knee implant infection; * Receive pathogen-appropriate antibiotic treatment from the study doctor; * If enrolled in Stage 1, receive active Sola2 AMF treatment at the designated sentinel temperature level; * If enrolled in Stage 2, receive either active Sola2 AMF treatment or sham AMF treatment, depending on randomization assignment; and * Complete follow-up visits and assessments for safety, infection status, pain, knee function, x-rays, laboratory tests, and other study-related outcomes.

Detailed description

The AMPLIFY trial is a prospective, multicenter, staged clinical investigation of the investigational Sola2 AMF Knee System in adults with confirmed knee periprosthetic joint infection (PJI) who will undergo debridement, antibiotics, and implant retention (DAIR) surgery and pathogen-appropriate antibiotic therapy.

The study is conducted under a single Investigational Device Exemption and includes two stages. Stage 1 is an open-label sentinel stage using sequential AMF temperature escalation. Sentinel participants receive active Sola2 AMF treatment, with safety review after each sentinel group before progression to the next planned temperature level or to the randomized stage. Stage 2 is a randomized, double-blind, sham-controlled stage in which participants are assigned to active Sola2 AMF treatment or sham AMF treatment.

The Sola2 AMF Knee System is an external, non-contacting investigational device that generates alternating magnetic fields intended to produce controlled heating at metallic knee implant surfaces. The AMF or sham treatment is administered in the operating room in conjunction with the planned DAIR procedure. All participants receive DAIR and pathogen-appropriate antibiotic therapy as part of their clinical care.

Safety oversight includes medical monitoring, independent Data Safety Monitoring Board review, and independent Clinical Events Committee adjudication as specified in the protocol.

Interventions

• Device Intervention 1: Alternating Magnetic Field Treatment
  Active alternating magnetic field treatment is delivered using the investigational Sola2 AMF Knee System. The system is an external, non-contacting device that generates alternating magnetic fields intended to produce controlled heating at metallic knee implant surfaces. Treatment is administered in the operating room in conjunction with DAIR.
• Device Intervention 2 - Sham Treatment
  Sham alternating magnetic field treatment is delivered during the randomized stage using the Sola2 AMF Knee System workflow. The sham treatment uses the same treatment timing and device-use steps as active treatment, without delivery of active alternating magnetic field energy
• Procedure Debridement, Antibiotics, Implant Retention
  Debridement, antibiotics, and implant retention is the planned surgical treatment for participants with knee prosthetic joint infection participants. In this study, all participants undergo DAIR, including polyethylene spacer exchange, and receive pathogen-appropriate antibiotic therapy as part of standard clinical care.

Primary outcome measures

• Change From Baseline in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement [Time frame: Baseline to 6 months]
• Incidence of Infection-Related Surgical Reintervention [Time frame: From the index DAIR procedure through the primary efficacy analysis, triggered when 24 adjudicated events have occurred and at least 100 participants have completed 12-month follow-up]
• Incidence of AMF Study Device-Related Adverse Events [Time frame: Through 12 months post-procedure]

Secondary outcome measures (9)

• Incidence, Severity, and Relatedness of Adverse Events and Serious Adverse Events [Time frame: Through 12 months post-procedure]
• Time to Resolution and Duration of PJI-Related Signs and Symptoms [Time frame: Through 12 months post-procedure]
• Proportion of Participants With Resolution or Marked Improvement of Infection-Related Symptoms [Time frame: Through 12 months post-procedure]
• Change From Baseline in Numeric Rating Scale Pain Score [Time frame: Baseline through 12 months post-procedure]
• Change From Baseline in Knee Injury and Osteoarthritis Outcome Score for Joint Replacement at Follow-Up Visits Over Time [Time frame: Baseline through 12 months post-procedure]
• Change From Baseline in Patient-Reported Outcomes Measurement Information System Patient-Reported Health Status [Time frame: Baseline through 12 months post-procedure]
• Change From Baseline and Time to Normalization of C-Reactive Protein [Time frame: Baseline through 12 months post-procedure]
• Change From Baseline and Time to Normalization of Erythrocyte Sedimentation Rate [Time frame: Baseline through 12 months post-procedure]
• Proportion of Participants Achieving Biomarker Normalization [Time frame: Through 12 months post-procedure]

Eligibility criteria

Inclusion criteria

Eligible participants must meet all of the following criteria:

• Adult male or female participant aged ≥ 22 years at the time of surgery.
• PJI diagnosis of "infected" knee per the 2018 MSIS Definition of Periprosthetic Hip and Knee Infection.
• Patient presents with PJI symptoms lasting for ≤ 45 days.
• Well-fixed and functioning prosthesis during clinical exam at screening.
• Patient to be treated with DAIR, polyethylene spacer exchange and pathogen- appropriate antibiotic therapy.
• Implanted knee prosthesis must appear on the "AMPLIFY Implant List".
• All implanted knee prosthesis components must have a legible device identification label (implant sticker) available in the medical record.
• Able to comprehend and comply with postoperative instructions and willing to return for follow-up visits for the duration of the study.
• Consent to participate in study and sign the Informed Consent Form (ICF).

Exclusion criteria

Participants meeting any of the following criteria will be excluded:

• Implanted knee prosthesis not appearing on the "AMPLIFY Implant List".
• Implanted knee prosthesis has any femoral and/or tibial augments, sleeves, cones, or modified/extended stems.
• Un-resurfaced patella.
• Metal-backed patellar components.
• Patients not indicated for a DAIR procedure pre-operatively.
• Patients undergoing bilateral DAIR procedures during the same surgical session.
• Pre-operative determination that the surgical wound cannot be closed primarily and requires a wound vac as a method of wound closure (e.g., open wound managed for secondary intention healing or delayed primary closure); Use of closed-incision negative pressure therapy over a primarily closed incision is permitted.
• Previous DAIR procedure(s) performed on the affected knee joint within the last two years.
• Patients presenting with PJI symptoms lasting for >45 days.
• Patients on antibiotic therapy for an infection other than PJI of the knee.
• Body Mass Index (BMI) ≥ 45.
• Patients currently on bone-marrow suppressive chemotherapy for malignancy.
• Patients currently with active neutropenia.
• Presence of metallic implant(s), other than the femoral and tibial components, within the Sola2 treatment zone (+/- 20 centimeters from the knee joint line) including intramedullary nails, hip prosthesis femoral stem, or fracture fixation hardware.
• Patients with an upper-thigh circumference greater than 70 centimeters (cm) (28 inches (in), measured approximately 15 cm (6 in) proximal to the superior pole of the patella.
• Patients with implanted or nonremovable cardiac pacemakers, defibrillators or cardioverters, insulin pumps, nerve stimulators, or any other indwelling infusion pump.
• Patients who are pregnant or nursing.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Sequential

Masking

Quadruple blind

Primary purpose

Treatment

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07700927 · SOL-200-2025

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗