Clinical and peri procedural outcomes using reduced dose prasugrel vs standard dose ticagrelor in elderly patients of acute coronary syndrome undergoing PCI
Authors: Nazir A , Vijay S K , Singh A K , Tiwari B C , Afroz E , Jamwal N , Jha A , Singh R , Thandi P , Qutubuddin Q 
Published: October 2024

Abstract

Introduction
The novel antiplatelet agent prasugrel is generally not indicated in elderly(&gt;75-years) patients in standard dose(60 mg loading and 10 mg maintenance) however, there is a scarce data on safety and efficacy of reduced dose prasugrel(30 mg loading and 5 mg maintenance dose) among elderly patients undergoing elective PCI. Some previous studies have raised concerns regarding the differences in pharmacodynamic and pharmacokinetic responses to prasugrel in asian ethnicities. The efficacy and safety of reduced dose prasugrel in elderly patients has not been investigated. Therefore, in this study we have compared the efficacy and safety of a reduced dose prasugrel with standard dose ticagrelor in elderly Indian patients undergoing elective PCI for acute coronary syndrome (ACS).

Purpose
To study the periprocedural and intermediate term clinical outcomes using reduced dose prasugrel versus standard dose ticagrelor in elderly Indian patients of acute coronary syndrome undergoing PCI.

Methods
This was a single centre, randomised, prospective cohort study. Based on the previous reference studies, at 95% level of significance and 80% of power, the sample size was calculated as 73 in each group. Study was conducted from May 2021 to October 2022 (18 months). Patients &gt;75 years of age with ST-segment–elevation (STE) or Non ST elevation (NSTE) ACS treated with PCI were included. The study was approved by the institutional ethics review board. Participants were assigned to receive a standard dose of ticagrelor (180 mg loading followed by 90 mg twice daily, n=73) or a reduced dose prasugrel (30 mg loading followed by 5 mg once daily, n=73). The primary efficacy end point of the study was a composite of major adverse cardiac events (MACE) including cardiovascular mortality , non fatal MI and stroke. The secondary safety end points were major and minor bleeding events. Patients were followed up at 15 days, 3 months and 6 months.

Results
The baseline clinical and demographic characteristics were comparable in the both groups. The composite of primary efficacy end points at 6 months occurred significantly more in ticagrelor group vs reduced dose prasugrel group(13.7% vs 4.1% P value=0.05) and composite of secondary safety end point were comparable in both the groups(21.9% vs 16.4% respectively, p=0.44). Dyspnoea was seen more frequently in standard dose ticagrelor group as compared to reduced dose prasugrel group (15.1% vs. 6.8% respectively, p value=0.133).

Conclusion
The results of our study indicate that the reduced dose prasugrel is safe in elderly patients, has similar bleeding events as compared to standard dose ticagrelor group and is better tolerated. The reduced dose prasugrel is significantly more efficacious as compared to standard dose ticagrelor in elderly patients in terms of reduced MACE events. Although large scale randomized studies may be warranted in such populations to draw a broader conclusion.Baseline characteristicsEnd results