Long-Term Follow-Up of TX200-TR101 (STEADFAST Long Term)

Long-Term Follow-Up of Patients Who Have Received an Autologous Antigen-Specific Chimeric Antigen Receptor T Regulatory Cell Therapy (CAR- Treg Therapy, TX200-TR101) in a Prior Clinical Study

This long-term follow-up study is being conducted to collect long-term (up to 15 years post-infusion) safety and tolerability data from subjects enrolled in studies evaluating TX200-TR101.

Study Overview

• Status: Active, not recruiting
• Conditions: End Stage Renal Disease; Kidney Transplant Rejection
• Intervention / Treatment: Diagnostic test: Blood sample

Detailed Description

This is long- term follow up observational trial for patients who participated previously to a multicentre, first-in-human, open-label, single ascending dose, dose-ranging study of autologous, chimeric antigen receptor T regulatory cells (CAR-Treg) in HLA-A2 mismatched living donor kidney transplant recipients, with a control cohort of mismatched kidney transplant recipients of similar immunological risk.

The aim is for this observational long-term follow up study (TX200-KT03) is to collect long-term (up to 15 years post-infusion) safety and tolerability data from subjects enrolled in studies evaluating TX200-TR101.

• Study Type: Observational
• Enrollment (Estimated): 11

Contacts and Locations

Study Locations

• Belgium
  • Leuven, Belgium
    • University Hospitals Leuven
• Netherlands
  • Groningen, Netherlands
    • University Medical Center Groningen
  • Leiden, Netherlands
    • Leiden University Medical Centre
  • Rotterdam, Netherlands
    • Erasmus MC, University Medical Center
• United Kingdom
  • Oxford, United Kingdom
    • Oxford University Hospitals NHS Foundation Trust

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Transplant recipients enrolled in the Phase I/IIa study (TX200-KT02) and who have consented to participate in this LTFU study,

Description

Inclusion Criteria:

1. Subjects who enrolled in the Phase I/IIa study TX200-KT02, received a transplanted kidney and have either completed or withdrawn from that study.
2. Willing and able to provide written informed consent (IC) in accordance with local regulations and governing Independent Ethics Committee (IEC)/Institutional Review Board (IRB) requirements prior to any procedure or evaluation performed specifically for the sole purpose of the study.

Exclusion Criteria:

• N/A

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Treatment group; Subjects underwent a kidney transplant as per planned standard of care and were administered study drug TX200-TR101 in study TX200-KT02 post transplantation Assigned interventions - subjects who received TX200-TR101 in clinical study TX200-KT02	Diagnostic test: Blood sample; Routine procedures
Control group; Subjects underwent a kidney transplant as per planned standard of care in study TX200-KT02 with no study drug administered	Diagnostic test: Blood sample; Routine procedures

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety and Tolerability of TX200-TR101 infusion evaluated by overall survival	Long term safety and tolerability of TX200-TR101 infusion evaluated by overall survival	Up to 15 years post infusion
Safety and Tolerability TX200-TR101 infusion evaluated by and incidence of serious adverse events (SAEs) according to CTCAE V5.0.	Long term safety and tolerability of TX200-TR101 infusion evaluated by and incidence of serious adverse events (SAEs) according to CTCAE V5.0.	Up to 15 years post infusion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Long term graft related outcomes	Incidence of graft rejection according to the Banff classification criteria	Up to 15 years post infusion
Number of in-patient days in hospital to evaluate the effect of TX200-TR101 over a long term	Number of in-patient days in hospital	Up to 15 years post infusion
Incidence of Adverse Events related to TX200-TR101 over a long term period	Incidence of Adverse Events related to TX200-TR101	Up to 15 years post infusion
Incidence of Adverse Events of special interest as defined in the protocol over long term	Incidence of Adverse Events of special interest as defined in the protocol	Up to 15 years post infusion
Change in immunosuppression regime to evaluate long term safety of TX200-TR101	Change in immunosuppression regime	Up to 15 years post infusion
Incidence of graft loss due to rejection to evaluate the composite efficacy profile of TX200-TR101	Incidence of graft loss due to rejection	Up to 15 years post infusion
Incidents of deaths to evaluate composite efficacy profile of TX200-TR101	Incidences of death of TX200-TR101 participants	Up to 15 years post infusion
Incidence of chronic graft dysfunction measured by changes in estimated glomerular filtration rate to evaluate the composite efficacy profile of TX200-TR101	Incidence of chronic graft dysfunction measured by changes in estimated glomerular filtration rate	Up to 15 years post infusion

Collaborators and Investigators

• Sponsor: Sangamo Therapeutics

Publications and helpful links

Helpful Links

• Link to parent study STEADFAST, TX200-KT02

Study record dates

Study Major Dates

• Study Start (Actual): August 15, 2023
• Primary Completion (Estimated): June 11, 2039
• Study Completion (Estimated): June 11, 2039

Study Registration Dates

• First Submitted: June 30, 2023
• First Submitted That Met QC Criteria: August 3, 2023
• First Posted (Actual): August 14, 2023

Study Record Updates

• Last Update Posted (Estimated): December 4, 2025
• Last Update Submitted That Met QC Criteria: December 3, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Cell Therapy; Chimeric antigen receptor; Long term follow up; Genetically modified cells; Regulatory T-Cells; T-Regs
• Additional Relevant MeSH Terms: Urogenital Diseases; Pathologic Processes; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Chronic Disease; Disease Attributes; Renal Insufficiency; Renal Insufficiency, Chronic; Pathological Conditions, Signs and Symptoms; Kidney Failure, Chronic; Investigative Techniques; Specimen Handling; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Punctures; Surgical Procedures, Operative; Blood Specimen Collection
• Other Study ID Numbers: TX200-KT03; 2022-002440-40 (EudraCT Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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