A Phase II, Double-Blind, Randomized, Placebo-Controlled, Multicenter Study Evaluating the Efficacy and Safety of Alpha-1 Antitrypsin (AAT) (Glassia®) in the Treatment of Recent-Onset Type 1 Diabetes.

Our aim was to assess the efficacy, safety, and tolerability of alpha-1 antitrypsin (AAT) as a therapeutic modality for ß-cell preservation in patients with recent-onset type 1 diabetes. Seventy type 1 diabetes patients (37 males; mean age 13.1 ± 4.1years) were randomized to treatment with 22 infusions of AAT (Glassia®) (60 or 120 mg/kg) or placebo. The primary outcome was the area under the curve (AUC) of C-peptide from a 2-h mixed-meal tolerance test after 52 weeks. At week 52, C-peptide was 0.9, 0.45, and 0.48 pmol/mL in the AAT-120, AAT-60, and placebo groups (p = 0.170 and p = 0.866 vs. placebo, respectively). The declines in C-peptide glycated hemoglobin (HbA1c) and the total insulin dose (U/kg) were similar across groups. Within the predefined 12-18-years subgroup, the C-peptide AUC decreased significantly in the placebo and AAT-60 groups (-0.34 and -0.54 pmol/mL, respectively, p < 0.01), with a borderline decrease in the AAT-120 group (-0.29 pmol/mL, p = 0.047). The mean HbA1c level was significantly lower in the AAT-120 group compared to the placebo (6.7% ± 0.9% vs. 8.2 ± 1.4%, p = 0.05), and a higher percentage of patients attained HbA1c ≤ 7% (75% vs. 25%, p = 0.05). AAT was tolerated well, with a similar safety profile between groups. The AAT intervention showed promise in the subgroup of adolescents with recent-onset type 1 diabetes. Further studies are warranted to determine the impact and proposed mechanism of action of AAT in ß-cell preservation.

DiaPep277 preserves endogenous insulin production by immunomodulation in type 1 diabetes.

DiaPep277 is an immunomodulatory peptide that arrests beta cell destruction in mouse models of type 1 diabetes mellitus (T1DM). This article extends an original pilot observation to two studies of 61 patients (age > 16 years), diagnosed with T1DM within 6 months, and with measurable beta cell function. Patients were treated with placebo (n = 27) or 1.0 mg DiaPep277 (n = 34). After 13 months, 1.0 mg Dia Pep277 treatment significantly (P = 0.02) preserved beta cell function as compared to the control with a trend for reduced HbA1c. This was achieved without an increase in insulin dose in the DiaPep277 group and with excellent safety. DiaPep277-treated patients also had fewer Th1 DiaPep277-specific T cells.

Evaluation of long-term treatment effect in a type 1 diabetes intervention trial: differences after stimulation with glucagon or a mixed meal.

OBJECTIVE: Endogenous insulin secretion, measured by C-peptide area under the curve (AUC), can be tested using both the glucagon stimulation test (GST) and the mixed-meal tolerance test (MMTT). This study compares these two stimulation methods using long-term data from patients newly diagnosed with type 1 diabetes or with latent autoimmune diabetes. RESEARCH DESIGN AND METHODS: A recently completed phase 3 intervention study with DiaPep277 demonstrated improved glycemic control and a significant treatment effect of glucagon-stimulated C-peptide secretion. Unexpectedly, MMTT failed to detect differences between the treated and control groups. Data from 343 patients in two balanced-randomized, double-blind, placebo-controlled, parallel-group trials of DiaPep277 were used to compare and correlate between GST- and MMTT-derived C-peptide AUC. Pearson's correlations were calculated for absolute C-peptide AUC at baseline and 12 and 24 months and for long-term changes in AUC (AUC). RESULTS: The absolute AUC values obtained at any single time point by the two tests were well correlated in both data sets (r = 0.74-0.9). However, the correlations between the AUC were much weaker (r = 0.39-0.58). GST-stimulated C-peptide secretion was stable over the fasting glucose range permitted for the test (4-11.1 mmol/L), but MMTT-stimulated C-peptide secretion decreased over the same range, implying differences in sensitivity to glucose. CONCLUSIONS: Measurement of long-term changes in stimulated C-peptide, reflecting endogenous insulin secretion, during the course of intervention trials may be affected by the method of stimulation, possibly reflecting different sensitivities to the physiological status of the tested subject.

Treatment of recent-onset type 1 diabetic patients with DiaPep277: results of a double-blind, placebo-controlled, randomized phase 3 trial.

OBJECTIVE: To evaluate safety and efficacy of DiaPep277 in preserving ß-cell function in type 1 diabetic patients. RESEARCH DESIGN AND METHODS: DIA-AID 1 is a multinational, phase 3, balanced-randomized, double-blind, placebo-controlled, parallel-group clinical study. Newly diagnosed patients (N = 457, aged 16-45 years) were randomized to subcutaneous injections of DiaPep277 or placebo quarterly for 2 years. The primary efficacy end point was the change from baseline in the area under the glucagon-stimulated C-peptide curve. Secondary end points were the change from baseline in mixed-meal stimulated C-peptide secretion and in fasting C-peptide and achieving target HbA1c ≤7% (≤53 mmol/mol). Partial remission (target HbA1c on insulin ≤0.5 units/kg/day) and hypoglycemic event rate were exploratory end points. RESULTS: DiaPep277 was safe and well tolerated. Significant preservation of C-peptide secretion was observed in the DiaPep277-treated group compared with the placebo (relative treatment effects of 23.4%, P = 0.037, and 29.2%, P = 0.011, in the modified intent-to-treat [mITT] and per-protocol [PP] populations, respectively). The mixed-meal stimulation failed to distinguish between the groups. There was a trend toward efficacy in fasting C-peptide levels, though not statistically significant. Significantly more DiaPep277-treated than placebo-treated patients maintained target HbA1c (mITT 56% versus 44%, P = 0.03; PP 60% versus 45%, P = 0.0082) and entered partial remission (mITT 38% versus 29%, P = 0.08; PP 42% versus 30%, P = 0.035). DiaPep277 treatment reduced the relative hypoglycemic event risk (mITT by 20%; PP by 28%). CONCLUSIONS: DiaPep277 safely contributes to preservation of ß-cell function and to improved glycemic control in patients with type 1 diabetes.

Immunomodulation with heat shock protein DiaPep277 to preserve beta cell function in type 1 diabetes - an update.

IMPORTANCE OF THE FIELD: Type 1 diabetes is a chronic autoimmune disease in which pancreatic beta cells are selectively destroyed. Ultimately hyperglycemia develops and insulin substitution becomes necessary. Immunomodulation aims at arresting this autoimmune attack. DiaPep277, the major T-cell epitope of heat shock protein 60 (hsp60), has been shown to be effective as a modulator of the immune system in type 1 diabetes and is the focus of this review. AREAS COVERED IN THIS REVIEW: A literature search of Pubmed listed publications covering 1990 - 2009 and a website search of the licensing company were performed. WHAT THE READER WILL GAIN: DiaPep277 has been successfully employed in animal models and has been investigated in Phase I - III studies in humans. A combined analysis of the Phase II trials showed a significant preservation of beta cell function in adults without adverse effects, but HbA1c was not changed. A Phase III clinical trial is ongoing, and a second Phase III trial will start in early 2010. Addressing the underlying autoimmune process is the call of the future in type 1 diabetes. TAKE HOME MESSAGE: Use of Diapep277 is a promising therapeutic strategy currently being tested in Phase III trials.