A Prospective Observational Study to Assess the Impact of Pharmacogenetics on Outcomes in Vascular Surgery (PROSPER)

IntroductionPatients with chronic limb threatening ischaemia (CLTI) are often prescribed clopidogrel in order to reduce their risk of major adverse limb and cardiovascular events. Clopidogrel is metabolised by the CYP2C19 enzyme, and genetics variations in CYP2C19 are common. These variants can influence an individuals ability to metabolise clopidogrel to its active metabolite. This work aims to establish the relationship between patient genotype and outcomes after revascularisation in patients with CLTI who are prescribed clopidogrel. It will consider whether pharmacogenetics can be used to ensure patients are prescribed effective medications to optimise their outcomes. Methods and analysisThis is a prospective observational cross-sectional study of patients undergoing lower limb surgical, endovascular or hybrid revascularisation for CLTI. Patients taking clopidogrel post-procedure, as well as those prescribed a non-clopidogrel based medication regimen, will be recruited prior to or shortly after revascularisation. Patients will undergo CYP2C19 genotyping and will be followed-up using online records. Ethics and disseminationManchester University Research Ethics Committee approval as obtained was part of the Implementing Pharmacogenetics to Improve Prescribing (IPTIP) trial process (IRAS 305751). The results of the study will be published in a peer-review journal and presented at international conferences. RegistrationThis work is a sub-protocol for the IPTIP study which is registered as ISRCTN14050335.