Implementing a pharmacogenetic-driven algorithm to guide dual antiplatelet therapy (DAPT) in Caribbean Hispanics: protocol for a non-randomised clinical trial

A novel machine learning model to predict high on-treatment platelet reactivity on clopidogrel in Asian patients after percutaneous coronary intervention

BACKGROUND

Various genetic and nongenetic variables influence the high on-treatment platelet reactivity (HTPR) in patients taking clopidogrel.

AIM

This study aimed to develop a novel machine learning (ML) model to predict HTPR in Chinese patients after percutaneous coronary intervention (PCI).

METHOD

This cohort study collected information on 507 patients taking clopidogrel. Data were randomly divided into a training set (90%) and a testing set (10%). Nine candidate Machine learning (ML) models and multiple logistic regression (LR) analysis were developed on the training set. Their performance was assessed according to the area under the receiver operating characteristic curve, precision, recall, F1 score, and accuracy on the test set. Model interpretations were generated using importance scores by transforming model variables into scaled features and representing in radar plots. Finally, we established a prediction platform for the prediction of HTPR.

RESULTS

A total of 461 patients (HTPR rate: 19.52%) were enrolled in building the prediction model for HTPR. The XGBoost model had an optimized performance, with an AUC of 0.82, a precision of 0.80, a recall of 0.44, an F1 score of 0.57, and an accuracy of 0.87, which was superior to those of LR. Furthermore, the XGBoost method identified 7 main predictive variables. To facilitate the application of the model, we established an XGBoost prediction platform consisting of 7 variables and all variables for the HTPR prediction.

CONCLUSION

A ML-based approach, such as XGBoost, showed optimum performance and might help predict HTPR on clopidogrel after PCI and guide clinical decision-making. Further validated studies will strengthen this finding.

Implementing a Pharmacogenomic-driven Algorithm to Guide Antiplatelet Therapy among Caribbean Hispanics: A non-randomized prospective cohort study

Background

After percutaneous coronary intervention (PCI), clopidogrel resistant patients are at an increased risk of major adverse cardiovascular and cerebrovascular events (MACCEs). We aimed to assess whether genotype-guided selection of oral antiplatelet drugs using a clinical decision support (CDS) algorithm reduces the occurrence of these ischemic events and improves outcomes among Caribbean Hispanic patients from Puerto Rico, who are underrepresented in clinical pharmacogenomic (PGx)-guided implementation studies.

Methods

Individual platelet function testing (PRU) measures, CYP2C19*2 and PON1 rs662 genotypes, clinical and demographic data from 8 medical facilities were included. Patients were separated into standard of care (SoC) and genotype-guided groups (150 each). Risk scores were calculated based on a previously developed CDS risk prediction algorithm designed to make actionable treatment recommendations for each patient. Alternative therapy with ticagrelor was recommended for patients with a high risk score ≥2. Statistical associations between patient time free of MACCEs and predictor variables (i.e., treatment groups, risk scores) were tested in this population using Kaplan-Meier survival analyses and Cox proportional-hazards regression models.

Results

Median age of participants is 67 years; BMI: 27.8; 48% women; 14% smokers; 59% with type-2 diabetes mellitus (T2DM). Among patients with high-risk scores who were free from MACCE events 6 months after coronary stenting, genotype-driven guidance of antiplatelet therapy showed superiority over SoC in terms of reducing the incidence rate of atherothrombotic events.

Conclusions

The clinical utility of our PGx-driven CDS algorithm to reduce the incidence rate of MACCEs among post-PCI Caribbean Hispanic patients on clopidogrel was externally demonstrated.

Clinical Trial Registration Unique Identifier

NCT03419325.

Advances and Perspectives in methods for identifying high platelet reactivity

Antiplatelet therapy is the foundational treatment for the prevention and treatment of coronary and cerebrovascular ischemic events in patients with coronary heart disease, ischemic stroke, and transient ischemic attack (TIA). However, with more and more studies reporting an increased risk of thrombosis in some patients due to poor response to therapeutic agents, the selection of appropriate P2Y12 inhibitors has become a major challenge that needs to be addressed urgently. Currently, commonly used oral P2Y12 inhibitors include clopidogrel, ticagrelor, and prasugrel. Assessing patients' risk factors before the development of treatment regimens by effectively predicting the risk of high platelet reactivity with specific P2Y12 inhibitors in advance to avert the occurrence of major adverse cardiovascular and cerebrovascular events (MACCE) is the key point to the problem. Up to now, methods available for predicting platelet reactivity include genetic testing, platelet function testing, and risk scores. This review provides a summarization of the existent available identification methods and analyzes the advantages and drawbacks of different methods in specific clinical settings, intending to guide the rational clinical application of P2Y12 receptor inhibitors.

Discovery of Ancestry-specific Variants Associated with Clopidogrel Response among Caribbean Hispanics

Background

High on-treatment platelet reactivity (HTPR) with clopidogrel is predictive of ischemic events in adults with coronary artery disease. Despite strong data suggesting HTPR varies with ethnicity, including clinical and genetic variables, no genome-wide association study (GWAS) of clopidogrel response has been performed among Caribbean Hispanics. This study aimed to identify genetic predictors of HTPR in a cohort of Caribbean Hispanic cardiovascular patients from Puerto Rico.

Methods

Local Ancestry inference (LAI) and traditional GWASs were performed on a cohort of 511 clopidogrel-treated patients, stratified based on their P2Y12 reaction units (PRU) into responders and non-responders (HTPR).

Results

The LAI GWAS identified variants within the CYP2C19 region associated with HTPR, predominantly driven by individuals of European ancestry and absent in those with native ancestry. Incorporating local ancestry adjustment notably enhanced our ability to detect associations. While no loci reached traditional GWAS significance, three variants showed suggestive significance at chromosomes 3, 14 and 22 (OSBPL10 rs1376606, DERL3 rs5030613, and RGS6 rs9323567). In addition, a variant in the UNC5C gene on chromosome 4 was associated with an increased risk of HTPR. These findings were not identified in other cohorts, highlighting the unique genetic landscape of Caribbean Hispanics.

Conclusion

This is the first GWAS of clopidogrel response in Hispanics, confirming the relevance of the CYP2C19 cluster, particularly among those with European ancestry, and also identifying novel markers in a diverse patient population. Further studies are warranted to replicate our findings in other diverse cohorts and meta-analyses.

Advantages of DES over BMS in Preventing the Risk of Myocardial Infarction, Ischemic Stroke, and Mortality in Various Populations

Backgrounds: Previous studies have demonstrated that drug-eluting stents (DESs) are more effective than bare metal stents (BMSs) in reducing the risk of myocardial infarction in the short term, but the long-term preventive benefits for myocardial infarction, ischemic stroke, and mortality are not clear. Objective: This study deeply analyzed the long-term (within 3 years) advantages of the use of DESs in preventing the risk of myocardial infarction, ischemic stroke, and mortality in various populations compared with those of using BMSs. Methods: This was a retrospective observational cohort study. We used the 2015-2019 claims data from Taiwan's National Health Insurance Research Database. Patients over the age of 18 who underwent coronary stent placement (both DESs and BMSs) for the first time in 2016 were included in the study population. Propensity-score matching was applied to increase the comparability of the DES and BMS groups. We used a Cox proportional hazard regression analysis to compare the effectiveness of DESs and BMSs in preventing myocardial infarction, ischemic stroke, and all-cause mortality. A subgroup analysis was also performed. Results: In total, 21,608 cases were included in this study. Overall, the risk of myocardial infarction (aHR = 0.82; 95% CI: 0.78-0.85), ischemic stroke (aHR = 0.88; 95% CI: 0.81-0.95), and mortality (aHR = 0.61; 95% CI: 0.57-0.65) in the DES group were significantly lower than those in the BMS group. However, in some special cases, the results were not statistically significant. In particular, in patients with obesity (aHR = 2.61; 95% CI: 1.20-5.69), the DES group appeared to have a significantly higher long-term intermediate ischemic risk than the BMS group. Conclusions and Relevance: In conclusion, although DESs were more effective than BMSs in reducing the risk of long-term myocardial infarction, ischemic stroke, and mortality, this study also found that, in some cases, the advantages of DESs over BMSs were not clearly observed.

Evaluation of race and ethnicity disparities in outcome studies of CYP2C19 genotype-guided antiplatelet therapy

Dual antiplatelet therapy with a P2Y₁₂ inhibitor (clopidogrel, prasugrel, or ticagrelor) and aspirin remains the standard of care for all patients undergoing percutaneous coronary intervention (PCI). It is well-established that patients carrying CYP2C19 no function alleles have impaired capacity to convert clopidogrel into its active metabolite and thus, are at higher risk of major adverse cardiovascular events (MACE). The metabolism and clinical effectiveness of prasugrel and ticagrelor are not affected by CYP2C19 genotype, and accumulating evidence from multiple randomized and observational studies demonstrates that CYP2C19 genotype-guided antiplatelet therapy following PCI improves clinical outcomes. However, most antiplatelet pharmacogenomic outcome studies to date have lacked racial and ethnic diversity. In this review, we will (1) summarize current guideline recommendations and clinical outcome evidence related to CYP2C19 genotype-guided antiplatelet therapy, (2) evaluate the presence of potential racial and ethnic disparities in the major outcome studies supporting current genotype-guided antiplatelet therapy recommendations, and (3) identify remaining knowledge gaps and future research directions necessary to advance implementation of this precision medicine strategy for dual antiplatelet therapy in diverse, real-world clinical settings.

Effects of CYP2C19 LoF allele on major adverse cardiovascular events associated with clopidogrel in acute coronary syndrome patients undergoing percutaneous coronary intervention: meta-analysis

The aggregated risk of major adverse cardiovascular events (MACE) in acute coronary syndrome (ACS) patients inheriting CYP2C19 loss-of function (LoF) alleles who underwent percutaneous coronary intervention (PCI) and were treated with clopidogrel is controversial. In the current study, we searched the literature in different databases for eligible studies. The risk ratio (RR) was measured where p<0.05 was statistically significant. The ACS patients with either one or two CYP2C19 LoF alleles who underwent PCI, treated with clopidogrel were correlated with a significantly escalated risk of MACE compared with noncarriers (RR: 1.53, 95% CI: 1.39-1.69, p<0.00001), driven by CV death (RR: 1.88, 95% CI: 1.18-3.01, p=0.008), MI (RR: 1.67, 95% CI: 1.21-2.31, p=0.002) and ST (RR: 1.90, 95% CI: 1.27-2.84, p=0.002). Patients with two CYP2C19 LoF alleles were correlated with significantly greater risk of MACE compared with noncarriers (RR: 3.91, 95% CI: 2.78-5.50, p<0.00001). Further analysis revealed that the risk of MACE was markedly significant in Asian patients (RR: 2.02, 95% CI: 1.67-2.44, p<0.00001) and was comparatively low significance in western patients (RR: 1.35, 95% CI: 1.20-1.52, p<0.00001). There was no significantly different bleeding events in patients with CYP2C19 LoF alleles compared with noncarriers (RR: 0.99, 95% CI: 0.85-1.15, p=0.87). The ACS patients inheriting CYP2C19 LoF alleles, who underwent PCI and were treated with clopidogrel were correlated with significantly increased risk of MACE compared with noncarriers.

Pharmacogenomic polygenic risk score for clopidogrel responsiveness among Caribbean Hispanics: A candidate gene approach

This multicenter clinical study was aimed at conducting a targeted pharmacogenomic association analysis of residual on-clopidogrel platelet reactivity in 474 Caribbean Hispanic patients. Platelet reactivity was measured using the VerifyNow P2Y12 assay and clopidogrel resistance was defined as P2Y12 reaction units (PRUs) greater than or equal to 208. Genotyping was performed using the whole-genome Infinium MEGA BeadChip array. An ancestry-adjusted, weighted polygenic risk score (wPGxRS) was developed to account for the effect of multiple variants on PRU and compared between clopidogrel responders and nonresponders. The mean PRU across the study cohort was 173.8 ± 68.5 and 33.5% of patients were defined as clopidogrel resistant. Multivariate linear regression showed that 19% of PRU variability was attributed to nine independent predictors, with CYP2C19*2 (rs4244285) accounting for ~ 7% of observed PRU variation (p < 0.001). PON1 rs662, ABCB1/MDR1 rs2032582, PEAR1 rs12041331 carrier status, and the interaction between African ancestry and rs12041331 carriers also predicted PRU among the participants (p ≤ 0.05). A clear gene-dose effect was detected between PRU and CYP2C19*2 genotype, consistent with previous studies in European patient populations, as well as rs12777823. Importantly, a significant positive correlation was detected between our novel wPGxRS (4 variants) and PRU among the Hispanic patient population (rp  = 0.35, p < 0.001). Moreover, the wPGxRS discriminated between nonresponders and responders (p = 0.003), indicating that this multigene-based score is a useful predictor of clopidogrel resistance among Caribbean Hispanics. Taken together, these results help close the gap of knowledge on clopidogrel pharmacogenomics and its potential clinical implementation in this under-represented population.

Utility of a pharmacogenetic-driven algorithm in guiding dual antiplatelet therapy for patients undergoing coronary drug-eluting stent implantation in China

PURPOSES

The POPular Risk Score (PRiS), a pharmacogenetic-driven algorithm consisting of CYP2C19 genotype, platelet reactivity, and clinical risk factors, is developed to evaluate ischemic risk and guide dual antiplatelet therapy (DAPT). This study aimed to evaluate the efficacy and safety of DAPT in accordance with the PRiS in patients undergoing drug-eluting stent (DES) implantation.

METHODS

A total of 1757 patients recruited in this cohort study were divided into four groups according to the PRiS and type of P2Y12 receptor inhibitor treatment at discharge. The primary endpoint was major adverse cardiovascular events (MACE, a composite of cardiovascular death, myocardial infarction, stroke, definite or probable stent thrombosis, and target vessel revascularization) during 1-year follow-up. The safety endpoints were defined by Bleeding Academic Research Consortium (BARC) criteria as major bleeding (BARC 3a, 3b, 3c, and 5) and clinically relevant bleeding (BARC 2, 3a, 3b, 3c, and 5).

RESULTS

Among 1046 patients with PRiS < 2 and 711 patients with PRiS ≥ 2, 34.2% and 38.3% of them were treated with ticagrelor, respectively. The PRiS ≥ 2 was an independent predictor for the 1-year incidence of MACE (HR(95%CI): 2.09 (1.37-3.20), p = 0.001). Multivariable Cox regression indicated that in the PRiS ≥ 2 group, ticagrelor was superior to clopidogrel in reducing the risk of MACE (HR(95%CI): 0.53 (0.29-0.98), p = 0.042), without increasing the bleeding risk. On the other hand, in the PRiS < 2 group, clopidogrel treatment was related to a remarkably lower rate of BARC class ≥ 2 bleeding (HR(95%CI): 0.39 (0.20-0.72), p = 0.003), but comparable incidences of MACE and BARC class ≥ 3 bleeding during 1-year follow-up. Similar associations between P2Y12 receptor inhibitors and 1-year endpoints in the PRiS < 2 and PRiS ≥ 2 group could also be identified in propensity score-weighted analysis and propensity score-matched analysis.

CONCLUSION

Tailored DAPT based on the PRiS could assist in improving the prognosis of patients undergoing DES implantation. Further randomized controlled trials are required to provide more evidence for PRiS-guided DAPT.