Treatment of Presymptomatic (Stage 1) Type 1 Diabetes Pediatric Patients With Treg Cell Preparations and Anti-CD20 Antibody (PreTreg)

January 14, 2026 updated by: PolTREG S.A.

A Multicenter, Randomized, Blinded, Placebo Controlled, Phase II Study to Evaluate the Safety and Efficacy of Cell Therapy Based With Artificially Expanded CD4+CD25+CD127- Regulatory Lymphocytes and Anti-CD20 Antibody in Pediatric Patients With Presymptomatic Diabetes Type 1 (Stage 1)

The main purpose of the study is to check:

  • Can therapy with a preparation of regulatory cells (Tregs lymphocytes) and/or an anti-CD20 antibody preparation (rituximab) be successfully used in children with pre-diabetes to treat or delay type 1 diabetes?
  • Is therapy with a preparation of regulatory cells (Tregs lymphocytes) and/or a preparation of antiCD20 antibodies (rituximab) safe for children with pre-diabetes, and what side effects may be associated with it? The study will include patients at high risk for type 1 diabetes whose laboratory tests have confirmed preserved normal/high insulin production. First (part 1 of the study), tests will be performed to determine the risk of the disease (determination of autoantibodies that characterize the autoimmune background).

In order to confirm the effectiveness of the therapy, not all patients will receive the study treatment. The study will be a so-called blinded randomized trial. This means that in this trial, all participants will undergo the same study procedures, but the participant will be randomly assigned to one of four (4) groups that will receive different treatment regimens before entering the study.

The participant will be randomly assigned to one of four groups:

  • Group I will receive a preparation of regulatory cells (Tregs lymphocytes) along with a preparation of antiCD20 antibodies,
  • Group II will receive a preparation of regulatory cells (Tregs lymphocytes) together with an inert substance (placebo)
  • Group III will receive a preparation of antiCD20 antibodies along with a sham treatment (inert substance)
  • Group IV will receive an agent containing an inert substance and sham treatment.

Approximately 150 patients aged 6-16 who are at risk of developing type 1 diabetes will be enrolled in the study, which will last up to 96 months. Each enrolled participant will remain in the study for up to five years.

Study Overview

Detailed Description

Participants: screening of approximately 2500 high-risk subjects will be conducted until no less than 150 participants with confirmed stage 1 (preclinical) type 1 diabetes mellitus are randomized; randomization 2:1:1:2; 50 participants treated with Tregs and anti-CD20 antibody; 25 participants treated with Tregs; 25 participants treated with anti-CD20 antibody; control: 50 participants receiving placebo and sham Tregs.

Inclusion of participants: up to 36 months. Trial intervention: Total duration of the trial intervention for each participant will be approximately 3 Months. After completion of the trial intervention, participants will be monitored at the sites for the onset of type 1 diabetes mellitus for a maximum of five years counting from the first dose of Tregs.

Follow-up time: post-treatment observation of all participants to 57 months (day "0" is the day of administration of the first dose of Treg/sham preparation).

Trial time: 96 months. Trial type: Prospective randomized (phase 2), placebo-controlled, parallel group, blinded trial.

Blinding: The following roles indicated below will not be made aware of the treatment group assignment during the trial:

  • participant
  • legal representatives
  • site staff excluding pharmacists (applies to anti-CD20only)

Study Type

Interventional

Enrollment (Estimated)

150

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Marta Druch, Clinical Trial Director
  • Phone Number: +48731471845
  • Email: m.druch@poltreg.com

Study Contact Backup

Study Locations

      • Bialystok, Poland, 15-269
        • Recruiting
        • Uniwersytecki Dzieciecy Szpital Kliniczny Im. L. Zamenhofa W Bialymstoku
        • Principal Investigator:
          • Artur Bossowski, prof
      • Gdansk, Poland, 80-211
        • Recruiting
        • Uniwersyteckie Centrum Kliniczne
        • Principal Investigator:
          • Matylda Hennig, Dr
      • Katowice, Poland, 40-752
        • Not yet recruiting
        • Gornoslaskie Centrum Zdrowia Dziecka Im. Sw. Jana Pawla II Samodzielny Publiczny Szpital Kliniczny Nr 6 Slaskiego Uniwersytetu Medycznego W Katowicach
        • Principal Investigator:
          • Przemyslawa Jarosz-Chobot, prof
      • Lodz, Poland, 90-419
        • Recruiting
        • Uniwersytet Medyczny w Lodzi
        • Principal Investigator:
          • Agnieszka Szadkowska, prof
      • Lublin, Poland, 20-093
        • Recruiting
        • Uniwersytecki Szpital Dzieciecy w Lublinie
        • Principal Investigator:
          • Iwona Ben-Skowronek, prof
      • Opole, Poland, 45-401
        • Recruiting
        • Uniwersytecki Szpital Kliniczny w Opolu
        • Principal Investigator:
          • Agata Chobot, prof
      • Rzeszów, Poland, 35-326
        • Recruiting
        • Centrum Medyczne Medyk Sp. z o.o. S.K.
        • Principal Investigator:
          • Artur Mazur, prof
      • Wroclaw, Poland, 50-556
        • Recruiting
        • Uniwersytecki Szpital Kliniczny im. Jana Mikulicza-Radeckiego we Wroclawiu
        • Principal Investigator:
          • Agnieszka Zubkiewicz-Kucharska, dr

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Age 6-16
  2. 25 ≤ BMI ≤ 75 percentile (acc. to OLAF) with a lower weight threshold of 20 kg
  3. Venous plasma glucose levels < 100mg% at fasting (70 to 100 mg/dl) and normal glucose tolerance test (at 120 minutes glycaemia <140 mg/dl) (acc. to PTD)
  4. Insulin independence
  5. C-peptide levels ≥ 1.0 ng/ml (central laboratory limit of normal) in fasting and post-stimulation tests increase ≥ 100%
  6. Participant has not yet been diagnosed with stage 2 or 3 type 1 diabetes mellitus (no history of dysglycemia, no history of clinical symptoms of type 1 diabetes mellitus)
  7. HbA1c level (%) <5,7% (acc. to ADA)
  8. Positive autoantibody titres (ICA, IAA, GAD, IA-2/ICA512, ZnT8) - low titers of two or more antibodies (2-4 times the normal*); if high titer of one of the antibodies (≥ 4 times the norm, not applicable to ICA) re-screening allowed (the participant can be included in the trial only after confirming two or more antibodies)
  9. Ability to give informed consent by the child's legal representatives (and the child himself or herself if he or she is over the age of 13 at the time of the trial [according to local law])
  10. Ability of the child's legal representatives to manage diabetes, defined as blood glucose levels control at least three times a day and the ability to dose insulin correctly.
  11. Venous access to guarantee blood donation

    Exclusion Criteria:

  12. Refusal to participate in the trial or lack of a signed informed consent form
  13. Suspicion or diagnosis for a type of diabetes other than type 1 diabetes mellitus
  14. Age under 6 or above 16
  15. IgA deficiency or history of other diagnosed immunodeficiency (max. 7 infections/year allowed, and the prognosis should indicate that the patient will remain in the study throughout its duration)
  16. C-peptide levels < 1.0 ng/ml fasting and in post-stimulation tests increase < 100%
  17. Glucose levels in venous blood ≥ 100mg% fasting
  18. Glucose levels in venous blood after 1 and 2 hours in OGTT ≥ 200mg%
  19. Glycated hemoglobin level (HbA1c) in venous blood ≥ 5,7%
  20. BMI < 25 or > 75th percentile for a given age or weight of less than 20 kg
  21. History of hypersensitivity to anti-CD20 or other components of the preparation
  22. History of hypersensitivity to penicillin and/or streptomycin
  23. Past or active infection with HBV, HCV, HIV, HTLV I/II, mycobacterium tuberculosis, syphilis. Laboratory evidence of infection without the need for clinical signs and symptoms is sufficient for diagnosis.
  24. Active infection with the EBV or CMV virus (positive IgM)
  25. Any fungal, parasitic, viral, or bacterial infection
  26. History of past or active cancer
  27. Anemia, lymphopenia, neutropenia, or thrombocytopenia defined as a blood cell count below the lower limit of normal for age found within the last 6 weeks prior to trial inclusion
  28. Elevated thrombotic activity/history of thrombosis episode
  29. Any disease prior to inclusion in the trial currently requiring medication for more than 3 months in history
  30. Diagnosed autoimmune disease other than type 1 diabetes mellitus, including a history of Hashimoto's disease and coeliac disease
  31. Taking anti-diabetic medication (including insulin) in the last 4 weeks prior to trial inclusion
  32. History of retinopathy
  33. History of hypertension
  34. Current or history of albuminuria
  35. For women in childbearing potential/menstruating women: pregnancy (from medical interview) or unwillingness to exercise sexual restraint or use effective forms of contraception for the duration of the trial and up to 4 months after completion, if applicable.

    The following contraceptive methods are acceptable: bilateral fallopian tube closure, sterilization in men, appropriate use of hormonal contraception that inhibits ovulation, hormone-releasing IUDs, and copper IUDs, male or female condoms with spermicide; and cap, uterine disc, or sponge with spermicide.

  36. Breastfeeding
  37. For males over 15 years of age: expressed intention to have offspring or donate sperm during the trial or within 4 months after the end of the trial, if applicable
  38. Excessive anxiety of the participant or his/her legal representatives regarding the procedures used in the trial
  39. Any medical problem that, in the opinion of the investigator, may adversely affect the participant's health if included in the trial
  40. Legal representatives and/or children over the age of 15 with an identified alcohol and/or psychoactive substance addiction
  41. History of disease of unknown etiology
  42. History of Creutzfeldt-Jacob disease
  43. History of progressive dementia or degenerative neurological disease, including of unknown origin
  44. History of taking hormones derived from the human pituitary gland (e.g., growth hormone)
  45. Treatment with immunosuppressants
  46. History of corneal, scleral, and dural transplant or undocumented neurosurgery
  47. History of occurrence of risk factors related to the participant's travel, where there is a possibility of exposure to regional infectious diseases
  48. Physical signs that indicate the risk of an infectious disease
  49. History of xenogeneic transplant

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: TregsCD20
Infusion of Treg preparation at "day 0" + 4 doses of antiCD20 antibody; second infusion of Treg preparation at time "+90±30days" Interventions: ex vivo expanded CD4+CD25+CD127- regulatory T cells (Tregs) + Anti-CD20 (rituximab)
regulatory T cells with the phenotype CD3(+)CD4(+)CD25(high)CD127(-)doublet(-)lin(-)
Other Names:
  • Tregs
  • regulatory T cells
rituximab
Other Names:
  • Mabthera
Placebo Comparator: Control group
Infusion of Treg sham at "day 0" + 4 doses of placebo; second infusion of Treg sham at time "+90±30days"
intrevenous 0,9% NaCl
intrevenous 0,9% NaCl
Experimental: Tregs only
Infusion of Treg preparation at "day 0" + 4 doses of placebo; second infusion of Treg preparation at time "+90±30 days"
regulatory T cells with the phenotype CD3(+)CD4(+)CD25(high)CD127(-)doublet(-)lin(-)
Other Names:
  • Tregs
  • regulatory T cells
intrevenous 0,9% NaCl
Experimental: CD20 only
Infusion of Treg sham at "day 0" + 4 doses of antiCD20 antibody; second infusion of Treg sham at time "+90±30days"
rituximab
Other Names:
  • Mabthera
intrevenous 0,9% NaCl

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of days from day 0 to the day of first dysglycemia (stage 2 of type 1 diabetes mellitus) in each group
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
To assess the safety and efficacy of the treatment used in the separate groups of participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/Tregs sham)
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Number of adverse events reported 1 year, 2 years after the first dose of Tregs and at the end of the trial
Time Frame: From enrollment to the end of participation in the trial at month 60 (day "0" is the day of administration of the first dose of Treg preparation)
To assess the safety and efficacy of the treatment used in the separate groups of participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/Tregs sham)
From enrollment to the end of participation in the trial at month 60 (day "0" is the day of administration of the first dose of Treg preparation)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of participants in each group who are in stage 2 type 1 diabetes mellitus, i.e., presence of autoantibodies, dysglycemia or stage 3 at year 1 and every year thereafter after the first dose of Tregs/placebo
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Total number of days from the date of diagnosis of stage 2 to the date of onset of full-blown type 1 diabetes mellitus (stage 3 of type 1 diabetes mellitus) in each group (normalized to the number of person/days in each group)
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
C-peptide levels [fasting/post MMTT stimulation (AUC) 1 year, 2 years after the first dose of Tregs and then annually until the end of the trial
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Daily dose of insulin per kg body weight (DDI) 1 year, 2 years after the first dose of Tregs, and annually thereafter until the end of the trial
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Number of participants in remission 1 year, 2 years after the first dose of Tregs, and annually thereafter until the end of the trial, [remission defined as daily insulin dose is less than 0.5U/kg/day with an HbA1c level less than 6.5%]
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Assessment of the incidence and severity of adverse events associated with the administration of Treg preparation or antiCD20 antibody, primarily the effects of immunosuppression: incidence of infections of any etiology and de novo tumors detected
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Percentage of participants in each group who are still in stage 1 type 1 diabetes mellitus, i.e., presence of autoantibodies and normoglycemia
Time Frame: From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60
Additional measures to assess the safety and efficacy of the treatment used in the separate groups of pediatric participants treated with combined treatment with Treg preparation and rituximab antibody or Treg preparation or rituximab antibody or the control (placebo/ Tregs sham) in preserving β-cell function
From day "0" (the day of administration of the first dose of Treg preparation) to the end of participation in the trial at month 60

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Study Director: Piotr Trzonkowski, Prof, PolTREG S.A.
  • Principal Investigator: Artur Bossowski, Prof, Uniwersytecki Dzieciecy Szpital Kliniczny Im. L. Zamenhofa W Bialymstoku
  • Study Chair: Wojciech Mlynarski, Prof, Uniwersytet Medyczny w Lodzi

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 12, 2025

Primary Completion (Estimated)

December 1, 2032

Study Completion (Estimated)

December 1, 2032

Study Registration Dates

First Submitted

November 12, 2024

First Submitted That Met QC Criteria

November 12, 2024

First Posted (Actual)

November 14, 2024

Study Record Updates

Last Update Posted (Estimated)

January 16, 2026

Last Update Submitted That Met QC Criteria

January 14, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

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

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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