CompletedNCT04662632APEXUpdated Apr 21, 2026Results posted

Abbreviated Protocol for Two-Stage Exchange

A Phase 2 interventional study of VT-X7 Treatment System with Tobramycin Sulfate and Standard of Care in Prosthetic Joint Infection, sponsored by Osteal Therapeutics, Inc.. Completed at 17 sites in United States. Open to participants aged 22 Years to 84 Years. Per ClinicalTrials.gov, last updated 2026-04-21.

Sponsored by Osteal Therapeutics, Inc. · Phase 2, Interventional, and Treatment

Phase: Phase 2
Study type: Interventional
Enrollment: 76
Allocation: Randomized
Ages: 22 Years to 84 Years
Sex: All

Study summary

Study Type: A multi-site, parallel group, randomized trial.

Study Objectives: The objective is to evaluate safety and determine preliminary efficacy of VT-X7 (Vancomycin and Tobramycin Exchanged over 7 Days). Efficacy is evaluated as superiority of the Experimental Arm in a composite endpoint of Overall Success at 90 days, consisting of a revision prosthesis implanted at Stage 2, patient survival, absence of reoperation and absence of periprosthetic joint infection (PJI). Secondary objectives are to evaluate superiority at 365 days in a composite endpoint of Overall Success, and in separate secondary endpoints for quality of life and patient survival. The exploratory objective is to compare Experimental and Control Arms in exploratory endpoints.

Follow-up: Patients will be evaluated at 90-, 180-, and 365-day follow-up visits.

Conditions studied

Prosthetic Joint Infection

Keywords

Hip
Knee
Biofilm
Minimum-biofilm-eradication-concentration

In context

Lead sponsor

Osteal Therapeutics, Inc. is the lead sponsor of 4 studies on the registry; none are open to participants now.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 22 Years to 84 Years
Sexes eligible: All
Accepts healthy volunteers: No

Inclusion criteria

Scheduled for two-stage exchange arthroplasty due to hip or knee PJI
Signed informed consent
22 to 84 years of age (inclusive)
Medical clearance for surgery
Preoperative diagnosis of PJI of the hip or knee per the International Consensus Meeting of Musculoskeletal Infection 2018 definition of Periprosthetic Hip and Knee Infection

Exclusion criteria

Exclusion Criteria:

Patients with 2 or more prior one-stage or two-stage exchange arthroplasties of the infected joint;
Patients with acute PJI, defined as total joint arthroplasty surgery within 4 weeks prior to enrollment (Stage 1) in this study;
Patients with bacteremia or positive bacterial blood culture in the last 30 days;
Patients with concurrent PJI of more than one joint;
Patients with ongoing active infection of an intravenous site;
Patients who require long-term anticoagulation or antiplatelet therapy, and for whom bridging or withholding therapy is not recommended based on the individual's clinical condition;
Patients with advanced renal insufficiency (chronic kidney disease Stage 4 or greater or glomerular filtration rate \<30 mL/min);
Patients on chemotherapy for malignant disease;
Patients on systemic glucocorticoid therapy (prednisone >10 mg/day or equivalent);
Patients with immunodeficiency (e.g., splenectomy, sickle cell anemia, Stage 3 human immunodeficiency virus infection, primary immunodeficiency disease, except immunodeficiency due to immunosuppressive therapy).
Patients who have an allergy to vancomycin hydrochloride or tobramycin sulfate (Note: prior history of red man syndrome is not considered an allergy);
Patients who have an allergy to titanium, titanium alloys, polymethylmethacrylate or polyurethane.
Patients who are pregnant or planning to become pregnant in the next 12 months;
Patients in whom negative pressure wound therapy is contraindicated;
Patients with a fungal PJI;
Patients who have a skeletal defect greater than 150 mm in length in the tibia or femur of the infected joint;
Patients who have a planned surgical procedure within 6 months of enrollment that can impact the conduct of the study;
Patients who are breastfeeding at the screening visit;
Patients who are incarcerated or are facing impending incarceration;
Patients who have been in treatment or referred for treatment for substance abuse within the past year;
Patients with any medical condition, including schizophrenia or another psychiatric disorder with hallucinations and/or delusions, that would interfere with the interpretation of the study results, the conduct of the study, or patient participation would not be in the best interest of the patient in the opinion of the Study Site Principal Investigator;
Patients who will participate in another clinical study of an investigational drug or investigational device or have participated in another clinical study of an investigational drug or investigational device within the past 30 days that would interfere with the interpretation of the study results or conduct of the study;
Patients who are judged by the Investigator to be unsuitable for the study.
Patients receiving immunosuppressive drug therapy for bone marrow or another transplant;
Patients currently or previously enrolled in this study;
Patients who receive therapy including any of the following biologic agents, which will not be withheld for a period beginning at least one dosing cycle (minimum 7 days) prior to Stage 1 surgery and ending at least 14 days following Stage 2 surgery:

Adalimumab (Humira) Tocilizumab (Actemra) Etanercept (Enbrel) Anakinra (Kineret) Golimumab (Simponi) Secukinumab (Cosentyx) Infliximab (Remicade) Ustekinumab (Stelara) Abatacept (Orencia) Rituximab (Rituxan) Certolizumab (Cimzia) Tofacitinib (Xeljanz) Belimumab (Benlysta)

Study design

Phase: Phase 2
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel assignment
Masking: Single (Participant)
Enrollment: 76 participants (actual)

Study arms

Experimental
Experimental
Local antibiotic irrigation via the VT-X7 (Vancomycin and Tobramycin Exchanged over 7 Days) Treatment System adjuvant to two-stage exchange arthroplasty per standard of care.
Combination Product: VT-X7 Treatment System with Tobramycin Sulfate · Procedure: Two-stage exchange arthroplasty · Combination Product: VT-X7 Treatment System with Vancomycin Hydrochloride
Active comparator
Control
Standard of care for treatment of chronic PJI - two-stage exchange arthroplasty: surgical removal of the infected implant, aggressive debridement, and exchange arthroplasty with administration of adjuvant systemic antibiotics and temporary antibiotic-impregnated cement spacer.
Drug: Standard of Care · Procedure: Two-stage exchange arthroplasty

Interventions

Combination productVT-X7 Treatment System with Tobramycin Sulfate
Seven-day local antibiotic irrigation with tobramycin sulfate via the VT-X7 Knee or Hip Spacer.
DrugStandard of Care
Forty-two days (minimum) systemic antibiotic administration adjuvant to two-stage exchange arthroplasty with temporary antibiotic-impregnated cement spacer per standard of care. Antibiotics will be selected by treatment provider and administered in accordance with national and local treatment guidelines.
ProcedureTwo-stage exchange arthroplasty
Stage 1 consists of surgical removal of the infected prosthesis, debridement, and implantation of a temporary spacer. Stage 2 surgery consists of explantation of the temporary spacer, debridement, and implantation of a permanent prosthesis, followed by systemic administration of postoperative antibiotics for 42 days (inclusive) to 90 days (inclusive).
Combination productVT-X7 Treatment System with Vancomycin Hydrochloride
Seven-day local antibiotic irrigation with vancomycin hydrochloride via the VT-X7 Knee or Hip Spacer.

What researchers measure

Primary outcomes

Composite Endpoint of Overall Success at 90 Days
Composite endpoint of Overall Success at 90 days consisting of: * Stage 2 revision prosthesis implanted; * Absence of PJI\* post-Stage 2; * Absence of reoperation\*\*\* of the affected joint pre- or post- Stage 2; and * Absence of mortality. * If clinical evidence of infection is present post-Stage 2 surgery, use the International Consensus Meeting on Musculoskeletal Infection 2018 guidelines for definitive PJI confirmation. * Reoperation includes only procedures to irrigate, debride, and remove or replace the Stage 1 spacer or any Stage 2 implant component.
Time frame: 90 days

Secondary outcomes

Composite Endpoint of Overall Success at 180 Days
Composite endpoint of Overall Success at 180 days consisting of: * Stage 2 revision prosthesis implanted; * Absence of PJI\* post-Stage 2; * Absence of continued antibiotic therapy for treatment or prophylaxis of PJI \*\*; * Absence of reoperation\*\*\* of the affected joint pre- and post-Stage 2; and * Absence of mortality. * If clinical evidence of infection is present post-Stage 2 surgery, use International Consensus Meeting on Musculoskeletal Infection 2018 guidelines for definitive PJI confirmation. * Continued antibiotic therapy includes antibiotic therapy at 180 days or beyond 12 weeks post-Stage 2 surgery, excluding antibiotics for documented pre-procedural prophylaxis or infection other than PJI. * Reoperation includes only procedures to irrigate, debride, remove or replace the Stage 1 spacer or any Stage 2 implant component.
Time frame: 180 days
Composite Endpoint of Overall Success at 365 Days Consisting of:
Composite endpoint of Overall Success at 365 days consisting of: * Stage 2 revision prosthesis implanted; * Absence of PJI\* post-Stage 2; * Absence of continued antibiotic therapy for treatment or prophylaxis of PJI \*\*; * Absence of reoperation\*\*\* of the affected joint pre- and post-Stage 2; and * Absence of mortality. * If clinical evidence of infection is present post-Stage 2 surgery, use International Consensus Meeting on Musculoskeletal Infection 2018 guidelines for definitive PJI confirmation. * Continued antibiotic therapy includes antibiotic therapy at 365 days or beyond 12 weeks post-Stage 2 surgery, excluding antibiotics for documented pre-procedural prophylaxis or infection other than PJI. * Reoperation includes only procedures to irrigate, debride, remove or replace the Stage 1 spacer or any Stage 2 implant component.
Time frame: 365 days

Results

Posted Apr 21, 2026

Participant flow

Participant flow — Overall Study
Milestone	VT-X7	Standard of Care
Started	37	39
Completed	34	34
Not completed	3	5

Outcome measures

PrimaryComposite Endpoint of Overall Success at 90 Days

Composite endpoint of Overall Success at 90 days consisting of: * Stage 2 revision prosthesis implanted; * Absence of PJI\* post-Stage 2; * Absence of reoperation\*\*\* of the affected joint pre- or post- Stage 2; and * Absence of mortality. * If clinical evidence of infection is present post-Stage 2 surgery, use the International Consensus Meeting on Musculoskeletal Infection 2018 guidelines for definitive PJI confirmation. * Reoperation includes only procedures to irrigate, debride, and remove or replace the Stage 1 spacer or any Stage 2 implant component.

Time frame:: 90 days
Reported as:: Count of participants · Participants

Composite Endpoint of Overall Success at 90 Days
Participants	VT-X7	Standard of Care
Composite Endpoint of Overall Success at 90 Days	33	11

Statistical analysis

VT-X7 vs Standard of Care · two-sided z-test for proportions · p = <0.0001

SecondaryComposite Endpoint of Overall Success at 180 Days

Composite endpoint of Overall Success at 180 days consisting of: * Stage 2 revision prosthesis implanted; * Absence of PJI\* post-Stage 2; * Absence of continued antibiotic therapy for treatment or prophylaxis of PJI \*\*; * Absence of reoperation\*\*\* of the affected joint pre- and post-Stage 2; and * Absence of mortality. * If clinical evidence of infection is present post-Stage 2 surgery, use International Consensus Meeting on Musculoskeletal Infection 2018 guidelines for definitive PJI confirmation. * Continued antibiotic therapy includes antibiotic therapy at 180 days or beyond 12 weeks post-Stage 2 surgery, excluding antibiotics for documented pre-procedural prophylaxis or infection other than PJI. * Reoperation includes only procedures to irrigate, debride, remove or replace the Stage 1 spacer or any Stage 2 implant component.

Time frame:: 180 days
Reported as:: Count of participants · Participants

Composite Endpoint of Overall Success at 180 Days
Participants	VT-X7	Standard of Care
Composite Endpoint of Overall Success at 180 Days	21	13

SecondaryComposite Endpoint of Overall Success at 365 Days Consisting of:

Composite endpoint of Overall Success at 365 days consisting of: * Stage 2 revision prosthesis implanted; * Absence of PJI\* post-Stage 2; * Absence of continued antibiotic therapy for treatment or prophylaxis of PJI \*\*; * Absence of reoperation\*\*\* of the affected joint pre- and post-Stage 2; and * Absence of mortality. * If clinical evidence of infection is present post-Stage 2 surgery, use International Consensus Meeting on Musculoskeletal Infection 2018 guidelines for definitive PJI confirmation. * Continued antibiotic therapy includes antibiotic therapy at 365 days or beyond 12 weeks post-Stage 2 surgery, excluding antibiotics for documented pre-procedural prophylaxis or infection other than PJI. * Reoperation includes only procedures to irrigate, debride, remove or replace the Stage 1 spacer or any Stage 2 implant component.

Time frame:: 365 days
Reported as:: Count of participants · Participants

Composite Endpoint of Overall Success at 365 Days Consisting of:
Participants	VT-X7	Standard of Care
Composite Endpoint of Overall Success at 365 Days Consisting of:	20	14

Adverse events

Collected over 1 year. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
VT-X7	2/36 (5.6%)	18/36 (50%)	36/36 (100%)
Standard of Care	4/40 (10%)	21/40 (52.5%)	40/40 (100%)

Most frequent serious events

Showing 10 of 38

Most frequent serious events
Event	VT-X7	Standard of Care
Device-related infectionInfections and infestations	4/36	3/40
Device dislocationProduct Issues	1/36	4/40
Wound dehiscence/haemorrhage/erosionInjury, poisoning and procedural complications	3/36	2/40
Joint dislocation/fractureInjury, poisoning and procedural complications	1/36	3/40
Device occlusionProduct Issues	2/36	0/40
Congestive cardiac failureCardiac disorders	2/36	1/40
HaematomaVascular disorders	0/36	2/40
Pulmonary embolism/oedemaRespiratory, thoracic and mediastinal disorders	1/36	2/40
Musculoskeletal foreign bodyInjury, poisoning and procedural complications	1/36	0/40
Post-operative anaemiaInjury, poisoning and procedural complications	1/36	0/40

Most frequent other events

Showing 10 of 36

Most frequent other events
Event	VT-X7	Standard of Care
Post-operative painInjury, poisoning and procedural complications	15/36	20/40
Post-operative anaemiaInjury, poisoning and procedural complications	18/36	15/40
Post-operative swellingInjury, poisoning and procedural complications	12/36	10/40
ArthralgiaMusculoskeletal and connective tissue disorders	8/36	11/40
Anaemia/Blood loss anaemiaBlood and lymphatic system disorders	9/36	5/40
Joint swellingMusculoskeletal and connective tissue disorders	3/36	8/40
NauseaGastrointestinal disorders	7/36	4/40
HypoaesthesiaNervous system disorders	6/36	4/40
Muscular weaknessMusculoskeletal and connective tissue disorders	6/36	1/40
Joint noise (clicking, crepitus)Musculoskeletal and connective tissue disorders	5/36	5/40

Baseline characteristics

Age, Continuous
Age, Continuous(Years)	VT-X7	Standard of Care	Total
Mean	65.7 ± 8.5	62.8 ± 8.9	64.7 ± 8.7

Sex: Female, Male
Sex: Female, Male(Participants)	VT-X7	Standard of Care	Total
Female	16	14	30
Male	21	25	46

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	VT-X7	Standard of Care	Total
American Indian or Alaska Native	0	0	0
Asian	0	0	0
Native Hawaiian or Other Pacific Islander	0	0	0
Black or African American	4	3	7
White	33	33	66
More than one race	0	2	2
Unknown or Not Reported	0	1	1

Study locations

17 sites

University of Arizona, Phoenix
Phoenix, Arizona 85004, United States
Harbor-UCLA Medical Center
Torrance, California 90502, United States
VA Medical Center
Washington D.C., District of Columbia 20422, United States
University of Florida
Gainesville, Florida 32611, United States
Cleveland Clinic
Weston, Florida 33331, United States
University of Kentucky
Lexington, Kentucky 40506, United States
Covenant Medical Center
Saginaw, Michigan 48602, United States
New York University
New York, New York 10003, United States
Columbia
New York, New York 10032, United States
OrthoCarolina Research Institute, Inc
Charlotte, North Carolina 28207, United States
Cleveland Clinic
Cleveland, Ohio 44195, United States
Ohio State University
Columbus, Ohio 43202, United States
Integris Southwest Medical Center
Oklahoma City, Oklahoma 73103, United States
Rothman Orthopaedic Institute
Philadelphia, Pennsylvania 19107, United States
Texas Health Presbyterian
Plano, Texas 75093, United States
University of Utah
Salt Lake City, Utah 84108, United States
UVA Orthopedics Center
Charlottesville, Virginia 22903, United States

References and documents

Publications

Springer BD, Higuera-Rueda CA, de Beaubien BC, Warner KD, Glassman AH, Parvataneni HK, Piuzzi NS. Safety Profile of Seven-Day Intra-articular Antibiotic Irrigation for the Treatment of Chronic Periprosthetic Joint Infection: A Prospective Randomized Phase II Comparative Study. J Arthroplasty. 2024 Sep;39(9 Suppl 1):S229-S235.e1. doi: 10.1016/j.arth.2024.03.069. Epub 2024 Apr 9. PubMed 38604274 ↗

Study documents

Protocol and statistical analysis plan · Oct 17, 2022

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Apr 21, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04662632
Lead sponsor: Osteal Therapeutics, Inc.
Responsible party: Sponsor
First posted: Dec 10, 2020
Start date: Nov 1, 2021
Primary completion: Mar 13, 2023
Completion: Dec 22, 2023
Results posted: Apr 21, 2026
Last update: Apr 21, 2026

Study contacts

Bryan Springer, MD

principal investigator · Ortho Carolina

Oversight

Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: Yes

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies from this sponsor

Osteal Therapeutics, Inc.

Start the discussion