Taking people in United StatesPhase 2

Tests anti-thymocyte globulin with or without verapamil in type 1 diabetes

Tests two drugs to help keep insulin production in young people with type 1 diabetes.

Key facts

Who runs it: University of Florida
Where: Aurora and Gainesville, United StatesSee the 2 sites
Trial code: NCT06455319
Registry title: Precision Administration of Anti-thymocyte Globulin With or Without Verapamil
Status: Recruiting
Phase: Phase 2
People taking part: 60 people, planned
Started: 12 Nov 2025
Expected to end: Aug 2030
Type of study: Interventional, 3 groupsOne group gets a placebo (a dummy treatment), for comparison.
Treatments tested: Anti-thymocyte globulin (ATG)
verapamil extended release capsule
Placebo
Record updated: 26 November 2025

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for children, teenagers and young adults with recently diagnosed type 1 diabetes who still make some of their own insulin.

Age: 6 to 35 years old.
Sex: All sexes can join.
Disease stage: Type 1 diabetes diagnosed less than 100 days before randomization. Stimulated C-peptide level of 0.2 pmol/ml on a mixed meal tolerance test done at least 21 days after diagnosis.
Earlier treatment: Must not have had ATG, verapamil or any investigational agent to delay beta cell loss in type 1 diabetes. Must be at least 6 weeks from the last live vaccine, and must have a killed flu vaccine at least 2 weeks before randomization when available.
Biomarker or test result: Positive for at least one islet cell autoantibody (GAD65A, mIAA, IA-2A, ICA or ZnT8A). EBV status is checked: people who are EBV seronegative need a negative EBV PCR within 30 days of randomization.

Main reasons for not taking part

Immune system weakness or low blood counts
Active infection, or past or current tuberculosis
Pregnant or breastfeeding, or planning pregnancy in the two-year study period
Current or past HIV, hepatitis B or hepatitis C infection
Needs other immunosuppressive drugs, or has had cancer other than skin cancer

The registry criteria, word for word

Show all 27 criteriaShow less

Who can take part

Must be >= 6 years <= 35
Must have a diagnosis of T1D for less than 100 days at randomization
Willing to provide Informed Consent or have a parent or legal guardian provide informed consent if the subject is <18 years of age
Positive for at least one islet cell autoantibody; GAD65A, mIAA, if obtained within 10 days of the onset of insulin therapy, IA-2A, ICA, or ZnT8A
Must have stimulated C-peptide levels of 0.2 pmol/ml measured during a mixed meal tolerance test (MMTT) conducted at least 21 days from diagnosis of diabetes. Randomization should occur within one month (37 days) of the MMTT
Subjects who are EBV seronegative at screening must be EBV PCR negative within 30 days of randomization and may not have had signs or symptoms of an EBV compatible illness lasting longer than 7 days within 30 days of randomization
Be at least 6 weeks from last live immunization
Participants are required to receive killed influenza vaccination at least 2 weeks prior to randomization when vaccine for the current or upcoming flu season is available
Be willing to forgo live vaccines during the treatment period and for 3 months following last dose of study drug
Be willing to comply with intensive diabetes management

Who cannot take part

Have evidence of prior or current tuberculosis infection as assessed by PPD, interferon gamma release assay or by history
Require use of other immunosuppressive agents including chronic use of systemic steroids
Current or ongoing use of non-insulin pharmaceuticals that affect glycemic control within prior 7 days of screening
Active participation in another T1D treatment study in the previous 30 days
Prior treatment with any investigational agent to delay beta cell loss in T1D
Prior treatment with ATG, Verapamil or known allergy to rabbit derived products
Have active signs or symptoms of acute infection at the time of randomization
Have evidence of current or past HIV, Hepatitis B or Hepatitis C infection
Have a history of malignancies other than skin
Known allergy to ATG or Verapamil
Any condition that in the investigator's opinion may adversely affect study participation or may compromise the study results
Be immunodeficient or have clinically significant chronic lymphopenia: (Leukopenia (< 3,000 leukocytes /μL), neutropenia (<1,500 neutrophils/μL), lymphopenia (<800 lymphocytes/μL), or thrombocytopenia (<100,000 platelets/μL)
Have any complicating medical issues or abnormal clinical laboratory results that may interfere with study conduct, or cause increased risk to include pre-existing cardiac disease, COPD, sickle cell disease, neurological, or blood count abnormalities
Evidence of liver dysfunction with AST or ALT greater than 3 times the upper limits of normal
Evidence of renal dysfunction with creatinine greater than 1.5 times the upper limit of normal
Be currently pregnant or lactating, or anticipate getting pregnant within the two year study period
Vaccination with a live virus within the last 6 weeks

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

Are you between 6 and 35 years old?

Where in United States

Barbara Davis Center for DiabetesAurora, United StatesContact: Kimber Simmons, MDTaking people
University of FloridaGainesville, United StatesContact: Jennifer L Hosford, MPHTaking people

About the trial

What the trial wants to find out

T cell directed therapy, anti-thymocyte globulin (ATG), in low doses, has been shown to lower HbA1c and preserve endogenous insulin production (measured by C-peptide) in individuals with recently diagnosed type 1 diabetes (T1D). However, not all individuals who received ATG responded to the therapy (i.e., non-responders). Additionally, use of ATG alone does not address inherent beta cell stress. A calcium channel blocker, verapamil, has demonstrated C-peptide preservation in newly diagnosed T1D. Investigators will identify those mostly likely to respond to ATG using an ex vivo predictive biomarker of response to ATG. In addition, Investigators will use sequential therapies to increase efficacy (ATG followed by verapamil) and explore synergistic mechanisms. This will be assessing with in depth immunophenotyping and quantify biomarkers of beta cell stress, cell death, and abnormal prohormone processing. Finally, novel clinical trial endpoints will be assessed for their ability to predict treatment efficacy earlier than the standard endpoint at 1 year.

The 3 groups in the trial

Anti-thymocyte globulin (ATG) intravenous infusionTreatment being tested
ATG (brand name Thymoglobulin) a polyclonal T cell antibody preparation. It will be given at low doses (0.5 mg/kg Day 1 then 2 mg/kg Day 2).
Treatment: Anti-thymocyte globulin (ATG)
Placebo-ATGPlacebo, for comparison
Saline placebo
Treatment: Placebo
verapamil extended release capsuleTreatment being tested
Open label administration at 120, 240 or 360 mg daily based on weight and ECG findings