Background Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are a major development in the prevention of cardiovascular disease (CVD) and is one of the most significant discoveries since the development of statin therapy. Administration of two human monoclonal antibodies to PCSK9 (alirocumab and evolocumab) can significantly reduce low-density lipoprotein cholesterol (LDL-c) concentrations, thus improving lipid management. Accordingly, guidelines on the specific indications for alirocumab and evolocumab usage have been released. This multicentre study aimed to estimate the proportion of patients treated for an acute myocardial infarction (MI) who could be considered for PCSK9 inhibitors under the current National Institute for Health and Care Excellence (NICE) lipid targets criteria.

Methods The records of 596 patients in two large hospitals in Liverpool, UK were analysed. Information was collected on lipid profiles during and after admission, lipid-lowering therapy and previous CVD.

Results At least 2.2% of patients were eligible for PCSK9 inhibitors post-MI under the current NICE guidance. Additionally, 29% of patients failed to achieve LDL-c concentrations <2.0 mmol/L despite maximum statin therapy and failed to meet eligibility for PCSK9 inhibitors as per the NICE criteria. This cohort represents a group of patients ‘in limbo’, in which statin therapy alone is not sufficient to reduce LDL-c.

Conclusions PCSK9 inhibitors are expensive and so their use must be highly selective. At present, in a real-world setting with ezetimibe underprescribing, ~2% of patients are eligible and a further 30% are deprived of benefit and improved outcomes by lack of optimisation and/or potential use of PCSK9 inhibitors.