STOP-T1D – ATG Prevention Study

Antithymocyte globulin (ATG) is commonly used to prevent transplant rejection. Early research showed that ATG improved blood glucose management and preserved pancreas function in people with recently diagnosed type 1 diabetes (T1D). The STOP-T1D trial will test if ATG can delay or prevent people moving from the from pre-symptomatic stage (Stage 2) to clinically diagnosed T1D (Stage 3).

Stage 2 T1D is when people have two or more autoantibodies and abnormal blood glucose levels. This indicates the immune system has already started attacking the body’s insulin-producing beta cells in the pancreas. These autoantibodies and abnormal blood glucose levels can be detected in a blood test by a health professional. The presence of these autoantibodies increases the risk of progressing to Stage 3 T1D, which is when clinical diagnosis of T1D occurs.

Read more about the 3 stages of T1D development.

Who can get involved

• Aged between 12 and 35 years.
• Be at high risk of progressing to Stage 3 T1D, determined by a positive screening blood test for antibodies and slightly elevated blood glucose.
• Up to date with immunisation schedule, including COVID-19 and flu boosters.
• Other markers indicative of high risk of progression to Stage 3 T1D.


The study medication in this trial is given by intravenous infusion (through a vein in the arm) on two consecutive days. For every three participants, two will receive ATG and one will receive placebo. The allocation of medication will be done randomly.

Study visits

The two treatment visits will take six to 10 hours for the infusion and a further two hours for monitoring (8-12 hours in total). Participants will visit the trial site two weeks after the second treatment, then every three to six months for one year. Participants will continue to visit the trial site for monitoring twice a year for up to four years following treatment.

Benefits of participation

In addition to potentially delaying or preventing progression of T1D, benefits to participating in the study include close monitoring and follow up by the research team. If you progress to Stage 3 T1D, the study blood tests will likely show this before any symptoms appear. Early diagnosis and commencement of insulin treatment largely eliminates the risk of a serious condition called diabetic ketoacidosis (DKA).

This trial is being undertaken by the JDRF-funded Australasian Type 1 Diabetes Immunotherapy Collaborative (ATIC).

To find out if you are eligible or if you have any questions contact the ATIC team.