Management of non-ST-elevation acute coronary syndromes: how cost-effective are glycoprotein IIb/IIIA antagonists in the UK National Health Service?

The glycoprotein IIb/IIIa antagonists (GPAs) represent a new class of drugs to prevent platelet aggregation in the acute treatment of non-ST-elevation acute coronary syndromes (NSTE-ACS). Systematic reviews have identified serious limitations in published cost-effectiveness analyses, including a lack of UK-specific studies and an absence of studies comparing different protocols for the use of GPAs. A model was developed to assess the cost effectiveness of a variety of protocols employing GPAs for patients presenting with NSTE-ACS in the UK. The perspective of the UK National Health Service was adopted, with outcomes in terms of quality-adjusted life-years (QALYs). Four treatment strategies were evaluated: GPAs as part of initial medical management (Strategy 1); GPAs in patients with planned percutaneous coronary interventions (PCIs; Strategy 2); GPAs as an adjunct to the PCI procedure (Strategy 3); and no GPAs (Strategy 4). Baseline event rates and costs were taken from a UK observational study of ACS patients and relative risk reductions from GPAs were taken from a meta analysis of trials. Long-term costs and QALYs were estimated using data from a UK longitudinal study. The most cost-effective use of GPAs is likely to be Strategy 1, with an incremental cost per QALY gained of between £4605 to £10,343. Focusing this use of GPAs only on the subgroup of patients at high risk appears to represent the most cost-effective use of NHS resources. Medical management of patients with NSTE-ACS using GPAs is the most cost-effective use of resources, particularly if targeted to higher risk subgroups.