BACKGROUND: This study aimed to analyse data from two different studies (Phase II and Phase III) regarding the safety and efficacy of treatment with alum formulated glutamic acid decarboxylase GAD65 (GAD-alum), 30 months after administration to children and adolescents with Type 1 diabetes (T1D).

METHODS: The Phase II trial was a double-blind, randomized placebo-controlled study, including 70 children and adolescents which were followed for 30 months. Participants received a subcutaneous injection of either 20 µg of GAD-alum or placebo at baseline and one month later. During a subsequent larger European Phase III trial including three treatment arms, participants received two or four subcutaneous injections of either 20 µg of GAD-alum and/or placebo at baseline, 1, 3 and 9 months. The Phase III trial was prematurely interrupted at 15 months, but of the 148 Swedish patients, a majority completed the 21 months follow-up and 45 patients completed the trial at 30 months. Both studies included GADA-positive patients with fasting C-peptide ≥0.10 nmol/l. We have now combined the results of these two trials.

RESULTS: There were no treatment related adverse events. In patients treated with 2 GAD-alum doses, stimulated C-peptide AUC had decreased significantly less (9 m: p < 0.037; 15 m p < 0.032; 21 m p < 0.003 and 30 m p < 0.004) and a larger proportion of these patients were also able to achieve a peak stimulated C-peptide >0.2 nmol/l (p < 0.05), as compared to placebo.

CONCLUSION: Treatment with two doses of GAD-alum in children and adolescents with recent-onset T1D shows no adverse events and preserves residual insulin secretion. This article is protected by copyright. All rights reserved.