Survival and Dialysis Independency in Highly Sensitized Patients After Desensitization With Imlifidase and Tx of Kidneys (ConfIdeSLTFU)

A Prospective, Long-term Confirmatory Follow up Trial in Highly Sensitized Patients Treated With Imlifidase or Standard of Care in the ConfIdeS (20-HMedIdeS-17) Trial

The goal of this follow-up study is to learn about long-term patient survival and graft function in highly sensitized patients who have received desensitization treatment with imlifidase or standard of care (SoC) in order to enable kidney transplantation in clinical study ConfIdeS (20-HMedIdeS-17, NCT04935177).

Study Overview

• Status: Active, not recruiting
• Conditions: Kidney Transplantation in Highly Sensitized Patients
• Intervention / Treatment: Drug: Imlifidase administered in the ConfIdeS study; Other: Best available treatment administered in the ConfIdeS study

Detailed Description

This is an observational follow-up study subsequent to the ConfIdeS study (20-HMedIdeS-17, NCT04935177) in highly sensitized patients who were randomized to imlifidase or SoC desensitization prior to kidney transplantation with a deceased donor graft, or, if SoC perioperative treatment has been deemed not appropriate, wait for a more immunologically compatible organ offer.

After the patients have given written informed consent to participate in the follow-up they will be included in the study and followed until 5 years after randomization in the ConfIdeS study.

Most of the assessments in this study are already part of the follow up within SoC for these patients. During the local clinic routine follow-up visits at year 2, 3 and 5 after randomization in the ConfIdeS study, information about patient survival, wait-list status, graft survival, kidney function, and health related quality of life will be evaluated.

• Study Type: Observational
• Enrollment (Estimated): 64

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35249
      • University of Alabama at Birmingham (UAB) Hospital
  • California
    • Los Angeles, California, United States, 90048
      • Cedars-Sinai Medical Center
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Northwestern University, Dept. General Surgery, Div. Transplantation
    • Chicago, Illinois, United States, 60637
      • University of Chicago, Department of Surgery, Clinical Research Center
  • Maryland
    • Baltimore, Maryland, United States, 21287
      • John Hopkins Hospital
  • Massachusetts
    • Boston, Massachusetts, United States, 02114
      • Massachusetts General Hospital
  • Missouri
    • St Louis, Missouri, United States, 63110
      • Washington University School of Medicine
  • New Jersey
    • Livingston, New Jersey, United States, 07039
      • Cooperman Barnabas Medical Center
  • New York
    • New York, New York, United States, 10032
      • Columbia University
    • New York, New York, United States, 10016
      • New York University (NYU) Langone Transplant Institute, NYU Langone Health
  • Texas
    • Houston, Texas, United States, 77030
      • Houston Methodist Hospital
    • San Antonio, Texas, United States, 78229
      • Methodist Hospital Specialty and Transplant
  • Washington
    • Seattle, Washington, United States, 98195
      • University of Washington Medical Center
  • Wisconsin
    • Milwaukee, Wisconsin, United States, 53226
      • Medical College of Wisconsin

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Patients who have participated in the clinical study ConfIdeS (20-HMedIdeS-17, NCT04935177)

Description

Inclusion Criteria:

1. Signed Informed Consent obtained before any trial-related procedures.
2. Previous participation in the clinical trial ConfIdeS.

Exclusion Criteria:

1. Inability by the judgement of the investigator to participate in the trial for any reason.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Imlifidase administered in the ConfIdeS study	Drug: Imlifidase administered in the ConfIdeS study; Imlifidase is an immunoglobulin G (IgG)-degrading enzyme of Streptococcus pyogenes that is highly selective towards IgG. The cleavage of IgG generates one F(ab')2- and one homodimeric Fc- fragment and efficiently neutralizes Fc-mediated activities of IgG.; Other Names: IdeS, HMED-IdeS
Best available treatment administered in the ConfIdeS study	Other: Best available treatment administered in the ConfIdeS study; Institution-specific desensitization treatment prior to kidney transplantation in the ConfIdeS study OR remain on wait list for a more compatible organ offer if desensitization with institutional protocol is not appropriate

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Proportion of patients alive and free of dialysis at 3 years	3 years after randomization in the ConfIdeS study

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients alive and free of dialysis at 5 years		5 years after randomization in the ConfIdeS study
Proportion of patients alive at 3 and 5 years		3 and 5 years after randomization in the ConfIdeS study
Graft failure-free survival rates at 3 and 5 years	Graft failure-free survival is defined as time from randomization to the fist of either graft failure or death	3 and 5 years after randomization in the ConfIdeS study
Graft survival rates at 3 and 5 years	To be assessed in patients who were transplanted at randomization in the ConfIdeS study	3 and 5 years after randomization in the ConfIdeS study
Number of patients per wait-list category	The different wait-list categories are: transplanted, active, temporary inactive, inactive, or deceased	3 and 5 years after randomization in the ConfIdeS study
Mean estimated glomerular filtration rate (eGFR) at 3 and 5 years	eGFR is a measure of kidney function. eGFR will be calculated based on p-creatinine according to the modification of diet in renal disease (MDRD) equation. Kidney disease is characterised by a decreased eGFR value. eGFR will be set to zero, for randomized patients who do not undergo transplantation, lose their graft or die.	3 and 5 years after randomization in the ConfIdeS study
Proportion of patients with biopsy- and serology confirmed antibody-mediated rejection (AMR)		3 and 5 years after randomization in the ConfIdeS study
Proportion of patients with biopsy confirmed cell-mediated rejection		3 and 5 years after randomization in the ConfIdeS study
Treatment of graft rejection episodes	Any treatments given during rejection episodes will be recorded	3 and 5 years after randomization in the ConfIdeS study

Collaborators and Investigators

• Sponsor: Hansa Biopharma AB
• Investigators: Study Director: Therese Åkerfeldt, Hansa Biopharma AB

Study record dates

Study Major Dates

• Study Start (Actual): April 21, 2023
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: January 27, 2023
• First Submitted That Met QC Criteria: January 27, 2023
• First Posted (Actual): February 6, 2023

Study Record Updates

• Last Update Posted (Estimated): November 18, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Desensitization; Renal transplantation; Highly sensitized; Positive crossmatch; Unlikely to be transplanted; Deceased donor
• Other Study ID Numbers: 21-HMedIdes-25

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: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No