Beta cell function during rapamycin monotherapy in long-term type 1 diabetes

Diabetologia. 2011 Feb;54(2):433-9. doi: 10.1007/s00125-010-1959-6. Epub 2010 Nov 3.

Abstract

Aims/hypothesis: Type 1 diabetes is considered non-reversible at end-stage disease when there is no measurable insulin production. However, there are indications that insulin-producing beta cells could be present or return if autoimmunity could be controlled. We therefore sought to determine whether immunosuppression therapy can reinstate beta cell function in patients with long-term type 1 diabetes.

Methods: We examined pancreatic beta cell function in 22 patients with long-term type 1 diabetes (median disease duration 27 years), who had been receiving rapamycin monotherapy (0.1 mg/kg; target trough levels 8-10 ng/ml; 26-314 days) as pre-conditioning for islet transplantation. As control, beta cell function was measured in 14 patients (median disease duration 17 years) who were waiting for an islet transplant without rapamycin pre-conditioning.

Results: Fasting C-peptide increased from <0.03 nmol/l (0.0066 nmol/l, interquartile range [IQR] 0.0003-0.023) at baseline to 0.039 nmol/l (IQR 0.0066-0.096) at end of rapamycin monotherapy (p < 0.005). In 12 patients, fasting C-peptide increased to >0.076 nmol/l (C-peptide responders). Exogenous insulin requirement decreased from 0.64 U/kg daily (IQR 0.56-0.72) to 0.57 U/kg (IQR 0.45-0.70; p = 0.01), but this reduction was significant only in the 12C-peptide-responsive patients. Rapamycin monotherapy was also associated with a decrease in insulin antibody titre (median decrease 110 to 35.9 U/ml; p < 0.001) and fasting serum proinsulin (median decrease 0.51 to 0.28 pmol/l; p = 0.001). All variables remained unchanged in the 14 control patients.

Conclusions/interpretation: Therapies to reinstate beta cell function may be applicable to patients with long-term C-peptide-negative type 1 diabetes.

Trial registration: ClinicalTrial.gov NCT01060605.

Publication types

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

MeSH terms

  • Adult
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Diabetes Mellitus, Type 1 / physiopathology*
  • Female
  • Humans
  • Immunosuppressive Agents / therapeutic use*
  • Insulin-Secreting Cells / physiology*
  • Male
  • Middle Aged
  • Proinsulin / blood
  • Sirolimus / therapeutic use*

Substances

  • Immunosuppressive Agents
  • Proinsulin
  • Sirolimus

Associated data

  • ClinicalTrials.gov/NCT01060605