Pexelizumab, an Anti-C5 Complement Antibody for Primary Coronary Revascularization: A New Insight from Old Versions

Pexelizumab, an anti-C5 complement antibody, as adjunctive therapy to reduce reperfusion injury after coronary revascularization in acute myocardial infarction and severe coronary artery disease had been approved in animal studies and further demonstrated clinical benefits in phase II study: the COMMA trial and phase III study: the PRIMOCABG trial. However, the negative results of pexelizumab were observed in the COMPLY trial and the APEX-AMI trial. In the APEX-AMI trial, the effectiveness of pexelizumab has reasoned to be prominent in high-risk patients. Similarly, an exploratory analysis of the combined PRIMO-CABG I and II data set using an established predictive risk model demonstrated a mortality benefit for high-risk surgical patients. Accordingly, the result of these trials supported a moderational model to explain the usefulness of pexelizumab affected by the baseline risk profiles of patients. In this regard, we have commented that pexelizumab may be hazardous to patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention without using adequate anti-thrombotic agents (glycoprotein IIb-IIIa antiplatelet inhibitors, clopidogrel and haparin non-responders) according to the results of the experiment by professor Røger and coworkers and the mathematic estimations of the relative risks. Herein, we proposed a mediational model to account for the effectiveness of pexelizumab.