title: Abciximab readministration: results of the ReoPro Readministration Registry.
abstract: BACKGROUND
  Platelet glycoprotein IIb/IIIa blockade with abciximab (ReoPro) improves the clinical outcomes of percutaneous coronary intervention. This registry was conducted to characterize the effects of repeated administration of abciximab during intervention.
  
  
  RESULTS
  We recruited 500 consecutive patients at 22 centers in the United States who were receiving abciximab for at least a second time during percutaneous coronary intervention. Safety was measured as the incidence of hypersensitivity reactions, major bleeding, and thrombocytopenia. Efficacy was assessed as event-free clinical success. Human antichimeric antibody (HACA) responses were also characterized. There were no cases of hypersensitivity (95% upper confidence bound, 0.3%), major bleeding, or death. Clinical success was 94.4%. Thrombocytopenia occurred in 23 patients (4.6%; 95% CI, 2.8% to 6.4%), including 12 (2.4%; 95% CI, 1.1% to 3.7%) who developed profound thrombocytopenia (<20x10(9) cells/L). In 2 patients (0.4%), profound thrombocytopenia did not develop until after hospital discharge; in 4 (0.8%), profound thrombocytopenia recurred despite platelet transfusion. Before a first readministration, a positive HACA titer was present in 22 of 454 patients (4.8%); after a first readministration, an additional 82 of 432 (19.0%) became HACA-positive. HACA did not neutralize the in vitro inhibition of platelet aggregation by abciximab or correlate with clinical events.
  
  
  CONCLUSIONS
  The results, including overall rates of thrombocytopenia, were consistent with randomized clinical trials of first abciximab treatment. However, there was a shift from mild to profound thrombocytopenia, and cases of delayed presentation and of recurrent thrombocytopenia were seen. These findings suggest that indications and guidelines for first-time use apply to retreatment, particularly the systematic monitoring for thrombocytopenia.
authors.affiliation: Duke Clinical Research Institute, Durham, NC, USA. tchen001@mc.duke.edu
authors.forename: J E
authors.initials: JE
authors.lastname: Tcheng
authors.forename: D J
authors.initials: DJ
authors.lastname: Kereiakes
authors.forename: A M
authors.initials: AM
authors.lastname: Lincoff
authors.forename: B S
authors.initials: BS
authors.lastname: George
authors.forename: N S
authors.initials: NS
authors.lastname: Kleiman
authors.forename: D C
authors.initials: DC
authors.lastname: Sane
authors.forename: D B
authors.initials: DB
authors.lastname: Cines
authors.forename: R E
authors.initials: RE
authors.lastname: Jordan
authors.forename: M A
authors.initials: MA
authors.lastname: Mascelli
authors.forename: M A
authors.initials: MA
authors.lastname: Langrall
authors.forename: L
authors.initials: L
authors.lastname: Damaraju
authors.forename: A
authors.initials: A
authors.lastname: Schantz
authors.forename: M B
authors.initials: MB
authors.lastname: Effron
authors.forename: G A
authors.initials: GA
authors.lastname: Braden
mesh_terms: D000077284:Abciximab; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects; D000906:Antibodies / Q000097:blood / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D001241:Aspirin / Q000008:administration & dosage; D003327:Coronary Disease / Q000097:blood / Q000628:therapy*; D018572:Disease-Free Survival; D004334:Drug Administration Schedule; D006470:Hemorrhage / Q000209:etiology; D006493:Heparin / Q000008:administration & dosage; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors; D011183:Postoperative Complications / Q000517:prevention & control; D012042:Registries / Q000706:statistics & numerical data*; D013921:Thrombocytopenia / Q000175:diagnosis* / Q000209:etiology; D016896:Treatment Outcome; D014481:United States; D014654:Vascular Patency / Q000187:drug effects*
chemical_list: D000906:Antibodies; D000911:Antibodies, Monoclonal; D007140:Immunoglobulin Fab Fragments; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D006493:Heparin; D001241:Aspirin; D000077284:Abciximab