Dimethyl fumarate to preserve insulin-producing beta cells in new-onset adult type 1 diabetes

A Single-Center, Randomized, Double-Blind, Placebo-Controlled Clinical Trial Evaluating the Efficacy and Safety of Dimethyl Fumarate in Preserving Islet β-Cell Function in Patients With Type 1 Diabetes Mellitus

This trial tests whether taking dimethyl fumarate twice daily can help preserve insulin-producing beta cells in adults recently diagnosed with type 1 diabetes.

Quick facts

• Phase: Phase 3
• Study type: Interventional
• Enrollment: 90 (estimated)
• Ages: 18 Years to 65 Years
• Sex: All
• Sponsor: Nanjing Medical University (Academic / other)
• Locations: 1 site (Nanjing, Jiangsu)
• Trial ID: NCT07258394 on ClinicalTrials.gov

What this trial studies

This randomized, placebo-controlled Phase 3 trial gives adults with new-onset type 1 diabetes either dimethyl fumarate or a matching placebo orally twice daily for 24 weeks, with on-site visits every 4 weeks during treatment and every 12 weeks afterward. Participants will record symptoms, blood glucose control, insulin use, and undergo measures of islet (beta) cell function including C-peptide. Safety monitoring will include liver enzymes and surveillance for infections or other adverse events. The primary goal is to compare preservation of beta-cell function between the treatment and placebo groups over the treatment and follow-up periods.

Who should consider this trial

Good fit: Adults 18–65 years old within 100 days of a type 1 diabetes diagnosis who are positive for at least two diabetes autoantibodies and have a random C-peptide ≥200 pmol/L are the intended participants.

Not a fit: People who are pregnant or breastfeeding, have long-standing diabetes, very low C-peptide, uncontrolled liver enzyme elevations, active infections, recent immune-modifying treatments, or other major exclusions are unlikely to benefit from this trial.

Why it matters

Potential benefit: If successful, dimethyl fumarate could slow loss of insulin-producing beta cells, potentially reducing insulin needs and improving blood glucose stability.

How similar studies have performed: Dimethyl fumarate has established immune effects in multiple sclerosis, but its use to preserve beta-cell function in type 1 diabetes is relatively novel and has not demonstrated conclusive success in prior T1D trials.

Eligibility criteria

Inclusion Criteria:

1. Subjects who provide written informed consent.
2. Aged 18-65 years.
3. Diagnosed with Type 1 Diabetes Mellitus (per ADA 2024 criteria).
4. Positive for ≥2 autoantibodies: Insulin autoantibody (IAA) Glutamic acid decarboxylase autoantibody (GADA) Protein tyrosine phosphatase antibody (IA-2A) Islet cell antibody (ICA) Zinc transporter 8 autoantibody (ZnT8A) Note: For IAA-positive subjects with insulin use \>14 days, ≥2 additional autoantibodies must be positive.
5. Disease duration ≤100 days post-T1DM diagnosis.
6. Random C-peptide ≥ 200 pmol/L.

Exclusion Criteria:

1. Pregnancy, lactation, or women of childbearing potential not using contraception.
2. Well-controlled glycemia with oral hypoglycemic agents alone.
3. Participation in other diabetes/immune-modulating trials.
4. ALT/AST \>3× upper limit of normal (ULN).
5. History of malignancy, uncontrolled autoimmune disorders, or active infections.
6. Alcohol/drug abuse, psychiatric disorders, or conditions unsuitable for trial participation.
7. Use of immunosuppressants within 12 weeks prior.
8. Participation in other drug trials within 12 weeks prior.
9. History of drug allergies, hypersensitivity, or drug addiction.
10. Any condition deemed by investigators to compromise study integrity.

Where this trial is running

Nanjing, Jiangsu

• Deparement of Endocrinology and Metabolism, The First Affiliated Hospital with Nanjing Medical University — Nanjing, Jiangsu, China (Recruiting)

Study contacts

• Study coordinator: Yong Gu

Conditions Type 1 Diabetes; Immunotherapy; Pancreatic Beta-Cell Function