Results of the controversial HEAT-PPCI trial is now published along with two commentaries supporting both the main findings and the ethics of the delayed consent strategy used in the study.
The study found that compared with bivalirudin, heparin reduces the incidence of major adverse ischaemic events in the setting of PPCI, with no increase in bleeding complications. It also revealed that systematic use of heparin rather than bivalirudin would reduce drug costs substantially.
However, when the trial was presented, it came under attack on two fronts: clinical results and ethics. But upon publication, it was bolstered by two supportive commentaries.
Peter Berger MD and James Blankenship MD of the Geisinger Health System in Danville, Pa said: "Most of the criticism has been based on inappropriate comparisons with trials that required use of a glycoprotein IIb/IIIa inhibitor with heparin, or that administered much larger doses of heparin," they wrote. "HEAT-PPCI provides strong evidence that bivalirudin alone compared with 70 U/kg of heparin alone (with infrequent bailout use of glycoprotein IIb/IIIa inhibitors in both arms), with radial access for STEMI percutaneous coronary intervention, seems to be inferior to heparin as administered in this trial."
"Even if heparin alone had produced statistically similar outcomes to bivalirudin, it would have been a win for heparin," they continued. "A drug that costs less than a 400th of another that has similar efficacy and safety ought be used preferentially."
The consent strategy involved in the trial was also heavily criticised but in his commentary, David Shaw PhD, of the University of Basel's Institute for Biomedical Ethics in Switzerland, said: "Far from being unethical, the study sets a high standard for consent in pragmatic trials."
"This strategy was preferable to attempting to obtain consent from potentially incompetent patients needing extremely urgent cardiac treatment. Delayed consent is recognized as an acceptable method of respecting patients' autonomy in emergency research in the Declaration of Helsinki," he wrote.
The Lancet, Early Online Publication, 5 July 2014