Antibodies against lepirudin are polyspecific and recognize epitopes on bivalirudin
Research article published in Blood (2004)
Abstract
Bivalirudin is a synthetic antithrombin sharing a sequence of 11 amino acids with the recombinant hirudin lepirudin. We investigated whether antilepirudin antibodies recognize epitopes on bivalirudin. Antilepirudin antibody-positive sera of 43 patients, treated with lepirudin for heparin-induced thrombocytopenia, were analyzed. Lepirudin- and bivalirudin-coated microtiter plates were used for antibody testing in an enzyme-linked immunosorbent assay (ELISA) system. Of the 43 sera-containing antibodies binding to lepirudin, 22 (51.2%) contained antibodies that also recognized bivalirudin. Binding of these antibodies to bivalirudin was inhibited by more than 70% by preincubation with high doses of bivalirudin. However, if lepirudin-coated microtiter plates were used, high concentrations of bivalirudin inhibited only 2 of the 43 positive sera by more than 30%. Therefore antihirudin antibodies must be polyspecific. The clinical consequences of this cross-reactivity are unknown but bivalirudin, targeted by antibodies of patients treated with lepirudin previously, could potentially boost antibody titers in such patients or even trigger an immune response by itself. Clinically significant antibody formation in response to bivalirudin monotherapy has not been observed, however. Yet, as lepirudin and antilepirudin antibodies have recently been implicated in severe anaphylactic reactions, caution is warranted when using bivalirudin in patients previously treated with lepirudin.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Peer-reviewed research on anticoagulant and antithrombotic drug development relevant to thrombin and factor inhibition. Indexed in PubMed and verified against the NCBI record.
Why This Matters for Hirudotherapy
This serological study tested whether antibodies raised against lepirudin (a recombinant form of the leech anticoagulant hirudin) also bind bivalirudin, a synthetic peptide that shares an 11-amino-acid stretch with lepirudin; of 43 antilepirudin-antibody-positive sera from heparin-induced-thrombocytopenia patients, 22 (51.2%) also recognized bivalirudin, indicating the antihirudin antibodies are polyspecific, though the authors note clinically significant antibody formation to bivalirudin monotherapy has not been observed. For hirudotherapy, this matters because it sits squarely in the leech-secretome drug-discovery lineage: hirudin from Hirudo medicinalis was the template for lepirudin, and this work maps the immunogenic overlap between that leech-derived molecule and a related thrombin inhibitor, informing how the secretome's translational descendants behave clinically. Honest caveat: this is a laboratory immunoassay study of stored patient sera, not a clinical-outcomes trial, so it characterizes antibody cross-reactivity and a theoretical caution rather than demonstrating real-world harm, and it speaks only to the hirudin-derived drugs, not to whole-leech therapy.
Citation
Antibodies against lepirudin are polyspecific and recognize epitopes on bivalirudin.
Eichler et al. · Blood, 2004
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