The Diabetes Prevention Trial of Type 1 Diabetes (DPT-1)
Condition: Diabetes Mellitus, Type 1
MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 1
Study type: Interventional
Phase: Phase 3

Summary: 
      The Diabetes Prevention Trial of Type 1 (DPT-1) was a multicenter randomized, controlled
      clinical trial designed to determine whether it is possible to delay or prevent the clinical
      onset of type 1 diabetes through daily doses of insulin in individuals determined to be at
      risk for the disease. Subjects were recruited from study clinics and through media
      campaigns.First-degree relatives, 3 to 45 years of age, and second-degree relatives, 3 to 20
      years of age, of patients with diabetes were screened for islet-cell antibodies. Those
      individuals found to be at high risk of diabetes were randomized to receive either close
      observation or low-dose parenteral insulin. Those individuals found to be at intermediate
      risk of diabetes are randomized to receive insulin orally or to receive placebo. Patients
      were followed for up to six years.
    

Detailed description: 
      The study was divided into three parts: screening, staging, and intervention. Subjects were
      recruited from study clinics and through media campaigns.First-degree relatives, 3 to 45
      years of age, and second-degree relatives, 3 to 20 years of age, of patients with diabetes
      were screened for islet-cell antibodies. Those with an islet-cell antibody titer of 10
      Juvenile Diabetes Foundation (JDF) units or higher were offered staging evaluations.

      Staging confirmed the presence of islet-cell antibodies, measured insulin antibodies,
      assessed the first-phase insulin response to intravenous glucose, assessed oral glucose
      tolerance, and determined the presence or absence of HLA-DQA1*0102, DQB1*0602, a protective
      haplotype, the presence of which excluded subjects from further participation.

      Islet-cell antibody-positive subjects were then defined as having a high risk of diabetes (a
      five-year risk of more than 50 percent) and were deemed eligible for the parenteral insulin
      trial if they had a first-phase insulin response below the threshold (as defined below) on
      two occasions, if their oral glucose-tolerance results were not completely normal,or both.

      Relatives who tested positive for islet-cell antibodies and insulin antibodies and who had a
      first-phase insulin response above the threshold and normal glucose tolerance were defined as
      having intermediate risk (a five-year risk of 26 to 50 percent) and were deemed eligible for
      the ongoing oral insulin trial.

      All randomized subjects were seen every six months, at which time an oral glucose-tolerance
      test was administered to assess glycemic status, the primary study end point. Mixed-meal
      tolerance tests were performed at base line, at years 1, 3, and 5, and at the end of the
      study. Intravenous glucose-tolerance testing was performed at years 2, 4, and 6 and at the
      end of the study.
    

Intervention name(s): Parenteral Insulin; Close Observation; Oral Insulin; Placebo
Intervention type(s): Drug; Other; Drug; Drug
Intervention description(s): Subcutaneous injections of recombinant human ultralente insulin in the morning and in the evening; the initial dose for each injection was 0.125 U per kilogram of body weight.; Study visits every 6 months including an oral glucose tolerance test; Capsules oral insulin, 7.5 mg of recombinant human insulin crystals; Placebo for oral insulin
Intervention MeSH terms: Insulin; Insulin, Globin Zinc
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: diabetes; insulin; prediction; prevention; C-peptide levels; insulin autoantibodies; pancreatic beta cell autoantibodies; cellular immune responses; prediction of type 1 diabetes