Effects of an anti-CD5 immunoconjugate (CD5-plus) in recent onset type I diabetes mellitus: a preliminary investigation. The CD5 Diabetes Project Team

J Diabetes Complications. Oct-Dec 1993;7(4):224-32.


Type-I (insulin-dependent) diabetes mellitus is an immunologically mediated disease that results in destruction of the insulin secreting beta cells of the pancreas. T cells have been implicated in the pathogenesis of this disease. One novel form of anti-T-cell therapy is the immunoconjugate CD5-Plus. This agent is composed of the murine IgG1 monoclonal antibody H65, which is directed toward the CD5+ antigen; and ricin A chain, a ribosomal inhibitor protein. We performed a pilot study to evaluate the safety of the immunoconjugate in subjects with type-I diabetes mellitus. We conducted a dose-escalation study using CD5-Plus given as an intravenous infusion for 5 consecutive days. Fifteen subjects (12 men and 3 women) with a mean age of 26 years, a mean duration of diabetes of 4.8 months, and a minimum stimulated C peptide of 0.3 pmol/mL were entered. Six subjects each were treated at the 0.1 and 0.2 mg/kg/day dosage levels, and three subjects were treated at the 0.33 mg/kg/day dose. Glycemic control was determined monthly by recording the glycohemoglobin, total daily insulin requirements, and fasting blood glucoses. Beta-cell function was measured by determining the C-peptide response to a mixed formula meal (Sustacal) at baseline and at 1,3,6,9, and 12 months after treatment. The area under the curve (AUC) of the C-peptide response was calculated and, to reduce variability, related to that of the same subject at baseline. An analysis of subjects who retained at least 80% of their baseline beta-cell function as measured by the AUC was performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Clinical Trial
  • Clinical Trial, Phase I
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antibodies, Monoclonal
  • Antigens, CD / blood
  • Antigens, CD / immunology*
  • C-Peptide / blood
  • C-Peptide / metabolism
  • CD5 Antigens
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / immunology
  • Diabetes Mellitus, Type 1 / therapy*
  • Female
  • Humans
  • Immunotoxins / therapeutic use
  • Immunotoxins / toxicity*
  • Insulin / metabolism
  • Insulin Secretion
  • Lymphocyte Depletion
  • Male
  • Regression Analysis
  • Ricin / therapeutic use
  • Ricin / toxicity*
  • T-Lymphocytes / immunology


  • Antibodies, Monoclonal
  • Antigens, CD
  • C-Peptide
  • CD5 Antigens
  • Immunotoxins
  • Insulin
  • Ricin