¹Pleun de Groen, ¹Coco M. Fuhri Snethlage, ²Sevilay Tokgöz, ¹Koen Wortelboer, ³Rick I. Meijer, ²Martin Gotthardt, ^{1, 4}Max Nieuwdorp, ^{1, 4}Nordin M.J. Hanssen

¹Department of Internal and Vascular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; ²Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands. ³Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands. ⁴Amsterdam Diabeter Center, Amsterdam, the Netherlands.

Background and aims. We recently showed that consequential autologous faecal microbiota transplantation (FMT), administered through a nasoduodenal tube, preserves beta cell function in new-onset type 1 diabetes (T1D). In this study, we aim to ease administration of autologous faeces and confirm feasibility of daily ingestion of lyophilized fecal microbiota capsules (LFMTc) for the preservation of residual beta-cell function in patients with recently diagnosed T1D

Materials and methods. This open-label, single-arm, single-centre pilot study included 10 subjects, 70% male, age 24.0±6.5 years, time in range (TIR) 92.5% [82.0-97.3], mean HbA1c 44.5±8.6 mmol/mol, mean fasting c-peptide of 0.21 [0.11-0.49] nmol/L, and median duration of T1Dof 2.0 [1.0-3.0] years. Participants took one autologous LFMTc a day between time point 0 and 3 months. Residual beta cell function was determined as the stimulated C-peptide release during two hours (AUC0-120min) after mixed meal test, performed at at -3, 0, 3 and 6 months.

Results. In the 3-month run-in phase, we observed a decline in beta cell function; nonetheless upon 3 month treatment with LFMTc’s the beta cell function remained stable. Notably, the beta cell secretory capacity was conserved for at least 3 months after stopping LFMTc treatment (Figure 1). Participants did not experience any serious adverse events.

Conclusion. LFMTc were safe and, similar to our previous study, seemed to halt the decline in endogenous insulin production up to 3 months after the LFMTc period in newly diagnosed patients with T1D. However, this is a pilot study and a larger randomized placebo-controlled trial is needed to confirm this effect.

Trial Registration Number

NCT05323162.

Funding

This study was made possible by the European Foundation for the Study of Diabetes.