Interference of thrombin in immunological assays for hirudin specific antibodies

J Immunol Methods. 2012 Jul 31;381(1-2):50-8. doi: 10.1016/j.jim.2012.04.008. Epub 2012 Apr 20.

Abstract

Recombinant hirudins (desirudin, lepirudin) are direct thrombin inhibitors administered as anticoagulants for heparin-induced thrombocytopenia (HIT) and venous thromboembolism (VTE) prophylaxis. Although these small polypeptides are widely used, concern exists over reports of antigenicity. In the largest study of r-hirudin immunogenicity to-date, we evaluated the prevalence, quantity and specificity of IgG immune responses to desirudin (15 mg SC q12h for as long as clinically required) in 245 surgical and medically-ill subjects enrolled in DESIRABLE, a multicenter, open-label, clinical trial of hospitalized patients requiring VTE prophylaxis. Sera obtained before and 30 days after desirudin administration were analyzed for IgG anti-desirudin by immunoenzymetric assay using immobilized desirudin to bind desirudin-reactive antibody and peroxidase conjugated monoclonal-anti-human IgG Fc to detect bound IgG antibody. Of 245 study subjects, 19 (7.7%) were antibody "responders" (>2-fold increase in IgG antibody levels with >50% inhibition by desirudin 30 days post-treatment). There were no differences between responders and non-responders in incidence of clinical outcomes or bleeding-related adverse events. Forty-six patients had detectable desirudin-reactive IgG antibody prior to treatment, with no significant increase in antibody levels after exposure and no increase in clinical events. The origin of pre-existing hirudin-reactive IgG antibody requires further investigation involving suspected anti-thrombin-thrombin interactions. These results indicate a low potential for immunogenicity, with <8% of patients developing IgG antibodies after desirudin administration for VTE prophylaxis. In contrast to reports on lepirudin, production of anti-hirudin antibodies to desirudin has no apparent effect on clinical events.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antibodies / blood
  • Antibodies / immunology*
  • Antibodies, Monoclonal / immunology
  • Antibody Specificity
  • Antithrombins / administration & dosage
  • Antithrombins / immunology
  • Female
  • Heparin / adverse effects
  • Hirudin Therapy
  • Hirudins / administration & dosage
  • Hirudins / genetics
  • Hirudins / immunology*
  • Humans
  • Immunoenzyme Techniques / methods*
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Male
  • Middle Aged
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Reproducibility of Results
  • Thrombin / immunology*
  • Thrombocytopenia / chemically induced
  • Thrombocytopenia / prevention & control
  • Time Factors
  • Venous Thromboembolism / chemically induced
  • Venous Thromboembolism / prevention & control

Substances

  • Antibodies
  • Antibodies, Monoclonal
  • Antithrombins
  • Hirudins
  • Immunoglobulin G
  • Recombinant Proteins
  • Heparin
  • Thrombin
  • desirudin