Safety and efficacy of the therapy with CD4 + CD25highCD127-T regulatory cells: When paediatric patient becomes adult.

AIM: CD4 + CD25highCD127-T regulatory cells (Tregs) remain a drug candidate for immunotherapy of type 1 diabetes. We completed three trials testing Tregs in recently diagnosed type 1 diabetes children. Here, we looked for long-term safety and efficacy aspects important in the authorisation of this therapy.

MATERIALS AND

METHODS

We re-examined 51 participants exposed to Treg therapy between 7.5 and 12 years prior to assessment. Based on previous assignments, we assessed the following subgroups treated with Tregs and anti-CD20 antibody (Tregs+antiCD20, N = 9), with 1 or 2 doses of Tregs only (Tregs 1 dose, N = 10 and Tregs 2 doses, N = 8). The exposed participants were compared with those who received standard of care therapy (SoC control, N = 24) as part of previous studies. The patients underwent diabetes-oriented tests as well as non- to minimal invasive evaluation of the anatomy and function of the eye, micro- and microcirculation, endocrine system, genitourinary tract and fertility, kidney and liver profiles, detailed biochemistry lab tests and safety screening. Over 700 variables were analysed.

RESULTS

Tregs+antiCD20 group was superior to SoC control group in terms of C-peptide secretion in mixed-meal tolerance test, the time of insulin independence and remission. No clinically relevant between-groups differences were found in other performed examinations. Importantly, no severe adverse effects including tumors or deaths were reported.

CONCLUSIONS

We confirmed the long-term safety and efficacy of the therapy. Due to the superior efficacy profile, the combined treatment with Tregs and antiCD20 antibody should be considered as a routine therapy for recent-onset type 1 diabetes patients.