13th November 2021, Dr Chee L Khoo
The authority to prescribe a PCSK9 inhibitors for patients with resistant hyperlipidaemia under the PBS continues to be pretty complicated. We tried to simplified those numerous criteria back in December 2020 here when the criteria were “loosened” somewhat. This has facilitated my prescription of this important drug in those patients who have really, really high cardiovascular risk. We now have a second agent on the block and they come with an app that makes the whole process a lot easier.
Alirocumab (Praluent) is the second PCSK9 inhibitor approved by the PBS for hereditary and non-hereditary familial hyperlipidaemia. Remember, proprotein convertase subtilisin kexin 9 (PCSK9) is an enzyme in the liver that block LDL-C receptors in the liver. These receptors are meant to remove LDL-C from circulation. PCSK9 inhibitors are monoclonal antibodies which bind and inactivate PCSK9 and thereby, reduce LDL-C levels.
When added to high-intensity or maximum-tolerated statin therapy after acute coronary syndrome (ACS), alirocumab reduced the first occurrence of the primary composite endpoint and was associated with fewer deaths relative to placebo in the ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) trial (1). Alirocumab reduced the first occurrence of the primary composite endpoint and was associated with fewer all-cause deaths in a trial of 18,924 patients. In patients with ACS, the total number of nonfatal cardiovascular events and deaths prevented with alirocumab was twice the number of first events prevented.
The initial prescription of Praluent still has to made by a specialist. Not all our patients are regularly followed up by a specialist, it is important that we find those patients that qualify for these agents. Praluent has created an app to assist GPs to identify which patients may qualify from Praluent and can prompt us to refer them a specialist to initiate a PCSK9 inhibitor. Alternatively, you could refer these patients to the Liverpool Lipid Clinic by faxing a referral to them.
The PBS criteria
Essentially, in a patient who has an LDL of >2.6 mmol/L despite maximally tolerated statins +/- ezetimibe, symptomatic ASCVD and the following:
- Patient must have atherosclerotic disease in two or more vascular territories (coronary, cerebrovascular or peripheral vascular territories); OR
- Patient must have severe multi-vessel coronary heart disease defined as at least 50% stenosis in at least two large vessels; OR
- Patient must have had at least two major cardiovascular events (i.e. myocardial infarction, unstable angina, stroke or unplanned revascularisation) in the previous 5 years; OR
- Patient must have diabetes mellitus with microalbuminuria; OR
- Patient must have diabetes mellitus and be aged 60 years or more; OR
- Patient must be an Aboriginal or Torres Strait Islander with diabetes mellitus; OR
- Patient must have a Thrombolysis in Myocardial Infarction (TIMI) risk score for secondary prevention of 4 or higher
……you should seriously consider referring your patient for initiation of a PCSK9 inhibitor.
Reference:
- G.G. Schwartz, P.G. Steg, M. Szarek, et al., for the ODYSSEY OUTCOMES Committees and Investigators. Alirocumab and cardiovascular outcomes after acute coronary syndrome N Engl J Med, 379 (2018), pp. 2097-2107