Clopidegrel resistance and outcomes in patients with ACS

 THESIS PROTOCOL

Submitted to the National Board of Examinations in Medical Sciences, New Delhi

Prevalence of CYP2C19 Genotype, Risk Factors and 90-Day Outcomes of Genotype-Guided Antiplatelet Therapy in patients with Acute Coronary Syndrome

Trainee’s Name: DR. SAI CHARAN KULKARNI

Specialty: DrNB (Cardiology)

Registration Number: __________

Year of Thesis: 2026

Name of Institute: DURGABAI DESHMUKH HOSPITAL & RESEARCH CENTER HYDERABAD.

Guide: ____________________

Co-Guide: ____________________

CONTENTS

Synopsis..................................................................................................................................... 1

Introduction................................................................................................................................ 2

Review of Literature.................................................................................................................. 4

Aim and Objectives................................................................................................................... 7

Material and Methods................................................................................................................ 8

References................................................................................................................................ 13

Appendix A: Case Record Form (Proforma)........................................................................... 15

Appendix B: Participant Information Sheet............................................................................ 19

Appendix C: Informed Consent Form..................................................................................... 22

Appendix D: Master Chart - Variable Coding Sheet............................................................... 25

Appendix E: Operational Definitions and Reference Tables.................................................. 26

Appendix F: Study Timeline................................................................................................... 27

Appendix G: Thesis Protocol Approval (TPA) Letter............................................................. 28

LIST OF ABBREVIATIONS

Abbreviation	Expansion
ACS	Acute coronary syndrome
ARC	Academic Research Consortium
BARC	Bleeding Academic Research Consortium
BMI	Body mass index
CI	Confidence interval
CPIC	Clinical Pharmacogenetics Implementation Consortium
CRF	Case record form
DAPT	Dual antiplatelet therapy
HTPR	High on-treatment platelet reactivity
ICCU	Intensive coronary care unit
ICF	Informed consent form
IEC	Institutional Ethics Committee
LOF	Loss-of-function
MACE	Major adverse cardiovascular events
NSTEMI	Non-ST-elevation myocardial infarction
PCI	Percutaneous coronary intervention
PFT	Platelet function test
PIS	Participant information sheet
STEMI	ST-elevation myocardial infarction

SYNOPSIS

Title: Prevalence of CYP2C19 Genotype, Risk Factors and 90-Day Outcomes in patient’s with Genotype-Guided Antiplatelet Therapy in Acute Coronary Syndrome

Background: Clopidogrel is a prodrug activated mainly by CYP2C19. Loss-of-function (LOF) alleles (*2, *3) reduce active metabolite formation and are linked to high on-treatment platelet reactivity, stent thrombosis and recurrent events. These alleles are common in South Asians, yet Indian outcome data are limited, heterogeneous and rarely prospective.

Aim: To describe the prevalence of CYP2C19 genotypic profile, clinical risk factors and 90-day outcomes of clopidogrel-treated patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI), and to examine the association of CPIC-concordant antiplatelet therapy with outcomes.

Methods: Prospective, open-label, single-centre observational cohort study in the Department of Cardiology (intensive coronary care unit and follow-up clinics) over 24 months. Consecutive adults with ACS undergoing PCI and started on clopidogrel are enrolled after written consent (n = 217). CYP2C19 genotyping (*2, *3, *17 by real-time PCR; sequencing of all coding exons) and platelet function testing are performed, and phenotypes are assigned per CPIC 2022. Treatment decisions remain with the treating cardiologist; concordance with CPIC recommendations is recorded. Follow-up is at 7, 30 and 90 days.

Outcome measures: Primary: allele and phenotype frequencies; 90-day major adverse cardiovascular events (MACE: all-cause death, non-fatal myocardial infarction, ischaemic stroke, definite or probable stent thrombosis). Secondary: association of LOF carriage with high on-treatment platelet reactivity (HTPR); BARC-defined bleeding; association of diabetes, body mass index, kidney disease, hypercholesterolaemia and age with outcomes within genotype strata.

Statistical analysis: Prevalence with 95% confidence intervals, Hardy-Weinberg testing, chi-square or Fisher exact tests, Kaplan-Meier curves with log-rank test, and multivariable (Firth) logistic regression, using IBM SPSS Statistics.

Expected outcome: Institutional genotype prevalence and preliminary outcome data to support genotype-guided antiplatelet selection in Indian ACS patients.

INTRODUCTION

Dual antiplatelet therapy (DAPT), combining aspirin with an oral P2Y12 inhibitor, is the cornerstone of secondary prevention after acute coronary syndrome (ACS) and percutaneous coronary intervention (PCI). For nearly two decades clopidogrel was the standard P2Y12 inhibitor. Ticagrelor and prasugrel give faster and more consistent platelet inhibition and are preferred by current guidelines in ACS.1,2

Clopidogrel is an inactive prodrug that needs two-step oxidation in the liver, in which CYP2C19 plays the central role. Loss-of-function (LOF) alleles, chiefly CYP2C19*2 and *3, reduce formation of the active metabolite and are associated with high on-treatment platelet reactivity (HTPR). In a meta-analysis of clopidogrel-treated patients, carriers of one LOF allele had about 1.5-fold higher risk of major adverse cardiovascular events (MACE) and 2.7-fold higher risk of stent thrombosis than non-carriers, and the risk was higher with two alleles.3

The distribution of these alleles varies with ancestry. CYP2C19 poor metabolisers account for about 15% of East Asians against about 3% of Europeans.4 Small Indian series report CYP2C19*2 carriage in nearly half of patients with coronary disease, and a substantial share of patients are intermediate or poor metabolisers.5,6 A large proportion of Indian ACS patients may therefore gain limited benefit from standard-dose clopidogrel.

Potent P2Y12 inhibitors are not a simple answer in India. In a single-centre Indian experience, ticagrelor was discontinued in 76.7% of patients, mostly at physician discretion and in about one in five because of cost.7 Clopidogrel therefore remains widely used, and identifying patients in whom it is likely to fail is clinically important. The CPIC guideline recommends prasugrel or ticagrelor for intermediate and poor metabolisers with ACS or PCI (strong recommendation),8 and the 2023 ESC guideline supports P2Y12 de-escalation (Class IIb) in patients unsuitable for potent inhibition.1

Indian data linking genotype, platelet reactivity and clinical outcome are scarce. Existing studies are small, use different assays and sampling times, and often lack prospective follow-up.5,6 This study addresses that gap in a prospective cohort of Indian ACS patients.

Research question: In Indian patients with ACS undergoing PCI and started on clopidogrel, what are the prevalence of CYP2C19*2, *3 and *17 polymorphisms, the associated clinical risk factors, and the 90-day clinical outcomes?

Hypotheses: (1) The prevalence of LOF allele (*2, *3) carriage exceeds the Western baseline of about 30%.3 (2) CPIC-concordant antiplatelet therapy is independently associated with lower odds of 90-day MACE after adjustment for clinical covariates. (3) Type 2 diabetes mellitus and higher body mass index are associated with higher on-treatment platelet reactivity in intermediate metabolisers.

REVIEW OF LITERATURE

Clopidogrel pharmacology and CYP2C19

Only a fraction of absorbed clopidogrel is converted, through two hepatic oxidative steps mediated mainly by CYP2C19, into the active thiol metabolite that irreversibly blocks the platelet P2Y12 receptor. In the TRITON-TIMI 38 cohort and in healthy volunteers, carriers of at least one reduced-function allele had lower exposure to the active metabolite and less platelet inhibition, and had higher rates of cardiovascular death, myocardial infarction, stroke and stent thrombosis than non-carriers.9

Response to clopidogrel can be measured as on-treatment platelet reactivity by the VASP phosphorylation platelet reactivity index (PRI), light transmission aggregometry or point-of-care assays. An international consensus defines high on-treatment platelet reactivity (HTPR) by a VASP-PRI above 50% and links it to ischaemic events.10 Results depend on the assay and on the timing of sampling, because measurements soon after PCI may be influenced by procedural stress and heparin; a steady-state sample on clopidogrel is therefore preferred.

Genotype distribution in Asian and Indian populations

In a global analysis of 141,614 individuals, CYP2C19 poor metabolisers made up about 15% of East Asians against about 3% of Europeans.4 In India, Shetkar et al. studied 110 patients with coronary artery disease on clopidogrel and found CYP2C19*2 in about 47%; LOF status was not associated with outcomes, but the sample was small and platelet function was not measured.5 Amarapalli et al. genotyped 60 patients in North India and classified about 37% as intermediate and 15% as poor metabolisers.6 The CYP2C19*17 allele increases enzyme activity, and CPIC advises standard-dose clopidogrel for rapid and ultrarapid metabolisers.8

Clinical consequences of LOF alleles

A meta-analysis of nine studies (9,685 patients) showed that, compared with non-carriers, patients with one reduced-function allele had higher MACE (hazard ratio [HR] 1.55; 95% CI 1.11-2.17) and stent thrombosis (HR 2.67; 95% CI 1.69-4.22), and those with two alleles had higher MACE (HR 1.76; 95% CI 1.24-2.50) and stent thrombosis (HR 3.97; 95% CI 1.75-9.02).3 Diabetes is associated with higher on-treatment platelet reactivity during clopidogrel therapy,11 and obesity has been proposed as a further modifier, although the evidence is less consistent.

Potent P2Y12 inhibitors

In PLATO (18,624 ACS patients), ticagrelor reduced the 12-month composite of vascular death, myocardial infarction or stroke compared with clopidogrel (9.8% vs 11.7%; HR 0.84; 95% CI 0.77-0.92), without an increase in overall major bleeding, although non-CABG-related major bleeding and dyspnoea were more frequent with ticagrelor.2 Higher potency thus carries a tolerability cost that may lead to premature discontinuation, which itself exposes the patient to stent thrombosis. In routine Indian practice, however, Senguttuvan et al. followed 309 ACS patients: ticagrelor was stopped in 237 (76.7%), with physician discretion accounting for 79.3% and cost for 18.6% of discontinuations.7

Genotype-guided antiplatelet therapy

POPular Genetics (2,488 patients with primary PCI for STEMI) showed that a genotype-guided strategy, in which LOF carriers received ticagrelor or prasugrel and non-carriers received clopidogrel, was non-inferior for net adverse clinical events (5.1% vs 5.9%) and caused less PLATO major or minor bleeding (9.8% vs 12.5%; HR 0.78; 95% CI 0.61-0.98).12 TAILOR-PCI (5,302 patients) tested escalation in LOF carriers: 12-month MACE was 4.0% vs 5.9% (HR 0.66; 95% CI 0.43-1.02; P = 0.06), and a post hoc analysis of the first 3 months showed HR 0.21 (95% CI 0.08-0.54).13

De-escalation strategies

Several trials show that early de-escalation of potent inhibitors reduces bleeding without an ischaemic penalty. In TOPIC (about 650 ACS patients), unguided switching to clopidogrel at one month lowered the composite of cardiovascular death, urgent revascularisation, stroke and BARC type 2 or higher bleeding (13.4% vs 26.3%), mainly through less bleeding.14 TALOS-AMI (2,697 patients) showed lower 12-month net adverse events with unguided de-escalation (4.6% vs 8.2%; HR 0.55).15 HOST-REDUCE-POLYTECH-ACS (2,338 patients) showed benefit with prasugrel dose reduction (7.2% vs 10.1%; HR 0.70),16 and TROPICAL-ACS (2,610 patients) showed non-inferiority of platelet-function-guided de-escalation (7.0% vs 9.0%).17 These trials enrolled mainly European and East Asian patients; South Asian patients were not specifically represented. Taken together, these data suggest that the early weeks after PCI carry the greatest thrombotic hazard for LOF carriers, whereas the later hazard of potent therapy is mainly bleeding, which supports a genotype-guided and time-aware approach.

Guidelines

The 2022 CPIC guideline recommends prasugrel or ticagrelor at standard dose for intermediate and poor metabolisers with ACS or PCI when there is no contraindication, and standard-dose clopidogrel for normal, rapid and ultrarapid metabolisers; the strength for intermediate metabolisers was raised to strong.8 The 2023 ESC guideline offers a Class IIb recommendation for de-escalation in patients unsuitable for potent platelet inhibition.1

Knowledge gap

Indian studies of clopidogrel response are small, differ in assay and timing of sampling, and seldom follow patients prospectively with standardised outcome definitions.5,6 Reported rates of clopidogrel non-response therefore vary with the test used, the interval after PCI and the sample size, and some studies have examined receptor genes rather than CYP2C19, the principal determinant of activation. A design that combines CYP2C19 genotyping, steady-state platelet reactivity and standardised 90-day outcomes can reduce these weaknesses. The prevalence of *2, *3 and *17 genotypes and their clinical correlates in Indian ACS patients, interpreted with CPIC-based therapy, therefore need prospective evaluation.

AIM AND OBJECTIVES

Aim: To describe the prevalence of CYP2C19 genotypic profile, associated clinical risk factors and 90-day clinical outcomes in clopidogrel-treated patients with acute coronary syndrome undergoing percutaneous coronary intervention, in relation to CPIC-guided antiplatelet therapy.

Primary objectives

1.      To determine the frequency of CYP2C19 alleles (*1, *2, *3, *17 and other variants found on exon sequencing) and metabolizer phenotypes (ultrarapid, rapid, normal, intermediate, poor) in the study cohort.

2.      To compare 90-day major adverse cardiovascular events between patients receiving CPIC-concordant and discordant antiplatelet therapy.

Secondary objectives

3.      To assess whether type 2 diabetes mellitus, hypercholesterolaemia, chronic kidney disease, age and body mass index are associated with high on-treatment platelet reactivity or events beyond genotype.

4.      To describe the trajectory of ischaemic events and BARC-defined bleeding at days 7, 30 and 90 across phenotype strata, and the correlation between them.

5.      To evaluate the association between LOF allele carriage and high on-treatment platelet reactivity.

MATERIAL AND METHODS

1. Study setting

Department of Cardiology of DURGABAI DESHMUKH HOSPITAL & RESEARCH CENTER, including the intensive coronary care unit (ICCU) and cardiology outpatient follow-up clinics. Genotyping and platelet reactivity assays will be performed at Third party vendor labs.

2. Study duration

Twenty-four months: months 1-2, IEC approval, case record form finalization, enrolment; months 3-23, 90-day follow-up of each participant; months 21-24, database lock, analysis and thesis writing (Appendix F).

3. Study design

Prospective, open-label, single-centre observational cohort study, reported according to the STROBE statement.18 No therapy is assigned by the investigators (Figure 1).

Figure 1. Study flow from enrolment to analysis.

4. Study sample

All consecutive eligible patients admitted during the enrolment period will be recruited (consecutive sampling). Eligibility will be assessed by the investigator after angiography. Consent will be sought once the patient is clinically stable, preferably before discharge from the ICCU and always within the index admission. Screened, eligible, consented and excluded patients will be logged, with reasons, to describe selection.

Inclusion criteria

•       Age 18 years or older at index admission.

•       Angiographically confirmed ACS (STEMI, NSTEMI or unstable angina) treated with PCI and requiring DAPT.

•       Current or planned clopidogrel as part of the initial DAPT regimen.

•       Written informed consent for genetic testing and follow-up for 90 days (with optional contact up to 12 months).

Exclusion criteria

•       Need for concurrent long-term oral anticoagulation (direct oral anticoagulant or vitamin K antagonist, for example for atrial fibrillation, deep vein thrombosis or mechanical valve).

•       Previous stroke of mechanism other than atherothrombotic large or small vessel disease (cardioembolic stroke, arterial dissection, cerebral vasculitis).

•       Known severe hepatic disease or abnormal baseline liver function tests, because clopidogrel activation is hepatic.

•       Inability or unwillingness to answer clinical questionnaires, or inability to attend follow-up.

•       Cardiogenic shock at presentation, or a known inherited or acquired platelet disorder (including platelet count below 100,000/µL).

5. Intervention and study procedures

Loading dose, choice of P2Y12 inhibitor, PCI technique and DAPT duration follow institutional protocol and the treating cardiologist’s judgement. Study procedures are: (a) 3 mL EDTA blood for genomic DNA; genotyping of CYP2C19*2 (rs4244285), *3 (rs4986893) and *17 (rs12248560) by allele-specific real-time PCR, and sequencing of all nine coding exons of CYP2C19 with flanking intronic sequence (reference NM_000769.4) to detect other variants; (b) 2 mL citrated blood for platelet function testing using ____________________ (assay to be specified), drawn 24-48 hours after the clopidogrel loading dose and before any switch of therapy; HTPR is defined by the consensus cut-off for the assay used.10 Diplotypes will be converted to phenotypes using the CPIC 2022 table (Appendix E).8 Variants of uncertain function give an indeterminate phenotype; such patients are described separately and excluded from the concordance analysis. The result will be reported to the treating cardiologist and entered in the medical record. Genomic DNA will be extracted by a column-based method and stored at -20°C; each run will include positive and no-template controls, and 10% of samples will be re-genotyped for quality assurance. Platelet function samples will be processed within the assay’s stability window. The treating cardiologist alone decides whether to act on the result; the reason for any non-concordant decision (cost, contraindication, bleeding risk, patient preference) will be recorded.

Therapy is classified as CPIC-concordant when intermediate or poor metabolisers receive prasugrel or ticagrelor, or normal, rapid or ultrarapid metabolisers receive clopidogrel; all other combinations are discordant.

6. Data collection

Data will be recorded on a case record form (Appendix A) from admission records, patient interview and laboratory reports: demographics, risk factors, presentation, laboratory values, angiographic and PCI details, antithrombotic therapy (including proton pump inhibitor use), genotype, platelet function result and treatment switches. Follow-up is at 7 (±2), 30 (±5) and 90 (±7) days by clinic visit or structured telephone interview using a standard script, covering symptoms, current P2Y12 inhibitor and dose, adherence (self-report and pill count), missed doses, bleeding, dyspnoea, readmissions and revascularisation. Events will be verified against hospital records, discharge summaries and, for deaths, caregiver report and death certificate. Participants lost to follow-up will be contacted at least three times and then censored at last contact. The CRF will be pilot-tested in the first 10 patients and staff trained in sampling and event definitions. Events will be adjudicated by two investigators not involved in treatment decisions and, where feasible, blinded to genotype and platelet function result.

7. Outcome measures

Primary: (a) frequencies of CYP2C19 alleles, genotypes and phenotypes; (b) 90-day MACE, a composite of all-cause death, non-fatal myocardial infarction,19 ischaemic stroke, and definite or probable stent thrombosis,20 assessed at 7, 30 and 90 days.

Secondary: (a) association of LOF allele carriage (*2, *3 and other no-function alleles) with HTPR and with clinical events; (b) any bleeding classified by BARC criteria over 90 days;21 (c) multivariable association of type 2 diabetes, age, body mass index, hypercholesterolaemia and chronic kidney disease with ischaemic outcomes across genotype strata; (d) composite of unplanned ischaemic readmission or repeat revascularisation. Definitions are in Appendix E.

8. Sample size

For estimating prevalence, n = Z²p(1-p)/d², with p = 0.46 (reported CYP2C19*2 carriage in Indian coronary artery disease patients),5 Z = 1.96 and absolute precision d = 0.07, giving 195 patients. Allowing 10% loss to follow-up, 217 patients will be enrolled. Scenarios with d = 0.05 (425 patients) and d = 0.08 (166 patients) were considered; d = 0.07 was chosen for feasibility within the 18-month enrolment period. Outcome comparisons are exploratory and not powered for definitive inference; with an expected 90-day MACE rate of 5-10%, about 11 to 22 events are anticipated.

9. Data management and statistical analysis

Data will be entered in a password-protected database under coded study identifiers, checked for completeness, and analysed with IBM SPSS Statistics (version 26 or later). Continuous variables will be summarised as mean (SD) or median (IQR) according to the Shapiro-Wilk test, and categorical variables as number (%). Two-sided P < 0.05 will be considered significant.

•       Objective 1: allele, genotype and phenotype frequencies (including other variants found on sequencing) with 95% CI; Hardy-Weinberg equilibrium by chi-square test; comparison of LOF carriage with the Western reference (30%) by one-sample proportion test.

•       Objective 2: 90-day MACE by CPIC concordance using chi-square or Fisher exact test; Kaplan-Meier curves with log-rank test; multivariable logistic regression reported as adjusted odds ratio (95% CI). Because few events are expected, covariates will be limited to about one per ten events and Firth penalised regression will be used. Model discrimination (area under the ROC curve) and calibration (Hosmer-Lemeshow test) will be reported.

•       Objective 3: univariable then multivariable logistic regression of risk factors for HTPR and events; exploratory genotype-by-diabetes and genotype-by-BMI interaction terms.

•       Objective 4: BARC bleeding and ischaemic events across phenotypes by chi-square or Fisher exact test.

•       Objective 5: platelet reactivity values across phenotypes by Kruskal-Wallis test; sensitivity, specificity and predictive values of LOF carriage for HTPR.

Missing data will be reported; complete-case analysis will be used with a sensitivity analysis for loss to follow-up.

10. Ethical issues

The study will begin only after approval by the Institutional Ethics Committee (IEC) and will follow the Declaration of Helsinki22 and the ICMR National Ethical Guidelines.23 Written informed consent, with a patient information sheet in English and the local language (Appendices B and C), will be taken before any study procedure; refusal will not affect care, and participants may withdraw at any time, with data retained up to withdrawal as stated in the consent form. Any adverse event related to venepuncture will be reported to the IEC. Risk is minimal and limited to venepuncture. Genetic testing is confined to the CYP2C19 gene, including sequencing of its coding exons; no whole-genome or whole-exome sequencing will be done and no other gene will be analysed. Participants will be identified by coded study IDs; the identification key will be restricted to the investigators, in line with the Digital Personal Data Protection Act, 2023.24 Samples will be used only for this study and destroyed after analysis or as the IEC directs. Funding: ____________________. Conflicts of interest: none.

Anticipated limitations: single-centre design limits generalisability; observational design cannot prove causality and residual confounding, including confounding by indication, is possible; few events limit multivariable analysis.

REFERENCES

Vancouver (ICMJE) style, numbered in order of first citation.

1.      Byrne RA, Rossello X, Coughlan JJ, Barbato E, Berry C, Chieffo A, et al. 2023 ESC Guidelines for the management of acute coronary syndromes. Eur Heart J. 2023;44(38):3720-826.

2.      Wallentin L, Becker RC, Budaj A, Cannon CP, Emanuelsson H, Held C, et al. Ticagrelor versus clopidogrel in patients with acute coronary syndromes. N Engl J Med. 2009;361(11):1045-57.

3.      Mega JL, Simon T, Collet JP, Anderson JL, Antman EM, Bliden K, et al. Reduced-function CYP2C19 genotype and risk of adverse clinical outcomes among patients treated with clopidogrel predominantly for PCI: a meta-analysis. JAMA. 2010;304(16):1821-30.

4.      Zhou Y, Lauschke VM. The genetic landscape of major drug metabolizing cytochrome P450 genes - an updated analysis of population-scale sequencing data. Pharmacogenomics J. 2022;22(5-6):284-93.

5.      Shetkar SS, Ramakrishnan S, Seth S, Chandna P, Verma SK, Bhargava B, et al. CYP 450 2C19 polymorphisms in Indian patients with coronary artery disease. Indian Heart J. 2014;66(1):16-24.

6.      Amarapalli J, Sharma P, Datta R, Sharma A. Implications of pharmacogenetic testing for clopidogrel therapy in a tertiary healthcare hospital in North India. Cureus. 2023;15(7):e42169.

7.      Senguttuvan NB, Sankaran R, Rajeev Y, Thaiyal D, Mathew A, Dharsini K, et al. Effect of discontinuation of ticagrelor and switching-over to other P2Y12 agents in patients with acute coronary syndrome: a single-center real-world experience from India. Egypt Heart J. 2021;73. doi:10.1186/s43044-020-00128-3.

8.      Lee CR, Luzum JA, Sangkuhl K, Gammal RS, Sabatine MS, Stein CM, et al. Clinical Pharmacogenetics Implementation Consortium guideline for CYP2C19 genotype and clopidogrel therapy: 2022 update. Clin Pharmacol Ther. 2022;112(5):959-67.

9.      Mega JL, Close SL, Wiviott SD, Shen L, Hockett RD, Brandt JT, et al. Cytochrome P-450 polymorphisms and response to clopidogrel. N Engl J Med. 2009;360(4):354-62.

10.    Tantry US, Bonello L, Aradi D, Price MJ, Jeong YH, Angiolillo DJ, et al. Consensus and update on the definition of on-treatment platelet reactivity to adenosine diphosphate associated with ischemia and bleeding. J Am Coll Cardiol. 2013;62(24):2261-73.

11.    Angiolillo DJ, Fernandez-Ortiz A, Bernardo E, Ramirez C, Sabate M, Jimenez-Quevedo P, et al. Platelet function profiles in patients with type 2 diabetes and coronary artery disease on combined aspirin and clopidogrel treatment. Diabetes. 2005;54(8):2430-5.

12.    Claassens DMF, Vos GJA, Bergmeijer TO, Hermanides RS, van ’t Hof AWJ, van der Harst P, et al. A genotype-guided strategy for oral P2Y12 inhibitors in primary PCI. N Engl J Med. 2019;381(17):1621-31.

13.    Pereira NL, Farkouh ME, So D, Lennon R, Geller N, Mathew V, et al. Effect of genotype-guided oral P2Y12 inhibitor selection vs conventional clopidogrel therapy on ischemic outcomes after percutaneous coronary intervention: the TAILOR-PCI randomized clinical trial. JAMA. 2020;324(8):761-71.

14.    Cuisset T, Deharo P, Quilici J, Johnson TW, Deffarges S, Bassez C, et al. Benefit of switching dual antiplatelet therapy after acute coronary syndrome: the TOPIC (timing of platelet inhibition after acute coronary syndrome) randomized study. Eur Heart J. 2017;38(41):3070-8.

15.    Kim CJ, Park MW, Kim MC, Choo EH, Hwang BH, Lee KY, et al. Unguided de-escalation from ticagrelor to clopidogrel in stabilised patients with acute myocardial infarction undergoing percutaneous coronary intervention (TALOS-AMI): an investigator-initiated, open-label, multicentre, non-inferiority, randomised trial. Lancet. 2021;398(10308):1305-16.

16.    Kim HS, Kang J, Hwang D, Han JK, Yang HM, Kang HJ, et al. Prasugrel-based de-escalation of dual antiplatelet therapy after percutaneous coronary intervention in patients with acute coronary syndrome (HOST-REDUCE-POLYTECH-ACS): an open-label, multicentre, non-inferiority randomised trial. Lancet. 2020;396(10257):1079-89.

17.    Sibbing D, Aradi D, Jacobshagen C, Gross L, Trenk D, Geisler T, et al. Guided de-escalation of antiplatelet treatment in patients with acute coronary syndrome undergoing percutaneous coronary intervention (TROPICAL-ACS): a randomised, open-label, multicentre trial. Lancet. 2017;390(10104):1747-57.

18.    von Elm E, Altman DG, Egger M, Pocock SJ, Gotzsche PC, Vandenbroucke JP. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Lancet. 2007;370(9596):1453-7.

19.    Thygesen K, Alpert JS, Jaffe AS, Chaitman BR, Bax JJ, Morrow DA, et al. Fourth universal definition of myocardial infarction (2018). Circulation. 2018;138(20):e618-51.

20.    Garcia-Garcia HM, McFadden EP, Farb A, Mehran R, Stone GW, Spertus J, et al. Standardized end point definitions for coronary intervention trials: the Academic Research Consortium-2 consensus document. Circulation. 2018;137(24):2635-50.

21.    Mehran R, Rao SV, Bhatt DL, Gibson CM, Caixeta A, Eikelboom J, et al. Standardized bleeding definitions for cardiovascular clinical trials: a consensus report from the Bleeding Academic Research Consortium. Circulation. 2011;123(23):2736-47.

22.    World Medical Association. World Medical Association Declaration of Helsinki: ethical principles for medical research involving human subjects. JAMA. 2013;310(20):2191-4.

23.    Indian Council of Medical Research. National ethical guidelines for biomedical and health research involving human participants. New Delhi: ICMR; 2017.

24.    Government of India. The Digital Personal Data Protection Act, 2023 (Act No. 22 of 2023). New Delhi: Ministry of Law and Justice; 2023.

APPENDIX A: CASE RECORD FORM (PROFORMA)

Study: CYP2C19 Genotype, Risk Factors and 90-Day Outcomes of Genotype-Guided Antiplatelet Therapy in Acute Coronary Syndrome

Study ID: ________    Date of enrolment: __/__/____    Hospital number: ________________

Section 1. Demographics and anthropometry

Item	Entry	Item	Entry
Age (years)		Sex	M / F
Height (cm)		Weight (kg)
BMI (kg/m²)		Residence / language

Section 2. Presentation

Item	Entry	Item	Entry
Diagnosis	STEMI / NSTEMI / UA	Symptom onset to admission (h)
Killip class		LVEF (%)
Troponin (peak)		ECG findings

Section 3. Risk factors and comorbidities

Risk factor	Y / N	Details	Value
Type 2 diabetes mellitus		Duration (years) / HbA1c (%)
Hypertension		Duration (years)
Hypercholesterolaemia / dyslipidaemia		LDL-C (mg/dL)
Chronic kidney disease		eGFR (mL/min/1.73 m²)
Smoking / tobacco		Type, pack-years
Prior MI / PCI / CABG		Specify
Prior stroke / TIA		Type
Family history of premature CAD
Proton pump inhibitor use		Drug and dose
Other CYP2C19-interacting drugs		Specify

Section 4. Baseline laboratory values

Test	Value	Test	Value
Haemoglobin (g/dL)		Platelet count (/µL)
Creatinine (mg/dL)		AST / ALT (U/L)
Total bilirubin (mg/dL)		Total cholesterol / LDL-C (mg/dL)
HbA1c (%)		Fasting glucose (mg/dL)

Section 5. Angiography and PCI

Item	Entry	Item	Entry
Culprit vessel		Number of vessels diseased
Stent type / number / length		Access site	Radial / Femoral
Final TIMI flow		GP IIb/IIIa inhibitor used	Y / N
Date and time of PCI		Complications

Section 6. Antithrombotic therapy

Item	Entry
Aspirin loading / maintenance dose
Clopidogrel loading dose and date/time
P2Y12 inhibitor at discharge	Clopidogrel / Ticagrelor / Prasugrel
Switch of P2Y12 inhibitor (date, from → to, reason)
Statin and dose

Section 7. Laboratory results

Item	Entry
EDTA sample date/time; report date
CYP2C19 genotype by real-time PCR (diplotype)	*1/*1   *1/*2   *1/*3   *1/*17   *2/*2   *2/*3   *2/*17   *3/*17   *17/*17   Other: ______
Other variants on exon sequencing (exon, change, function)
CPIC phenotype	UM / RM / NM / IM / PM / Indeterminate
Citrate sample date/time (hours after loading dose)
Platelet function test: assay, result (units)
HTPR (per assay cut-off)	Y / N

Section 8. CPIC concordance

Item	Entry
CPIC-recommended therapy for this phenotype
Therapy actually received
Concordant / Discordant	Concordant / Discordant
Reason if discordant	Cost / Contraindication / Bleeding risk / Patient choice / Result unavailable / Other

Section 9. Follow-up

Item	Day 7	Day 30	Day 90
Date; mode (visit / phone)
Current P2Y12 inhibitor and dose
Adherence (missed doses)
Death (date, cause)
Myocardial infarction
Ischaemic stroke
Stent thrombosis (definite / probable)
Unplanned readmission / revascularisation
Bleeding (BARC type)
Dyspnoea
Drug discontinued (reason)

Section 10. Adjudication

Primary MACE (Y / N): ____    Date of event: ____    Adjudicators: 1) ____________  2) ____________

APPENDIX B: PATIENT INFORMATION SHEET

Title of the study: Prevalence of CYP2C19 Genotype, Risk Factors and 90-Day Outcomes in patients with Genotype-Guided Antiplatelet Therapy in Acute Coronary Syndrome

Investigators: Principal investigator (trainee): DR. SAI CHARAN KULKARNI; Guide: ____________; Co-guide: ____________. Contact: ____________.

1. Why is this study being done? You have had a heart attack or unstable angina and a stent has been placed. You will take two blood-thinning (antiplatelet) medicines, one of which is often clopidogrel. In some people the body does not convert clopidogrel into its active form properly because of a variation in a gene called CYP2C19. This study aims to find how common this variation is in our patients and how patients do over the next 90 days.

2. What will happen if I take part? About 5 mL of blood will be drawn from a vein for the CYP2C19 gene test and a platelet function test. Your doctor will receive the results and decide, with you, whether your medicines should change. We will record information from your hospital file and will contact you at about 7, 30 and 90 days by clinic visit or telephone. We may also contact you once at 12 months to ask about your health.

3. Which gene will be tested? Only the CYP2C19 gene. To find changes that affect clopidogrel, all the coding regions (exons) of this gene will be read (sequencing). Your whole genome or exome will not be sequenced, no other gene will be examined, and no information about other diseases will be looked for.

4. Risks. Drawing blood may cause brief discomfort, a small bruise or, rarely, local swelling of the vein. There are no other added risks from the study.

5. Benefits. You may not benefit directly. The result may help your doctor choose a suitable antiplatelet medicine for you. The study may help future patients.

6. Costs. The study tests are done at no charge to you. You will not be paid for taking part. [Confirm per IEC.]

7. Confidentiality. Your name will not appear in any report. Your information will be stored under a code number, with the key held only by the study team, in line with the Digital Personal Data Protection Act, 2023. Your blood sample will be used only for this study and then destroyed as approved by the Ethics Committee.

8. Voluntary participation. You may refuse or withdraw at any time without giving a reason, and your treatment will not be affected.

9. Questions. You may ask us anything before or during the study. Contact the investigator above or the Member Secretary, Institutional Ethics Committee: ____________.

Telugu version – Patient Information Sheet

అధ్యయన శీర్షిక: అక్యూట్ కరోనరీ సిండ్రోమ్‌లో జన్యు-ఆధారిత యాంటీప్లేట్‌లెట్ చికిత్స: CYP2C19 జన్యురూపం, ప్రమాద కారకాలు మరియు 90 రోజుల ఫలితాలు

పరిశోధకులు: ప్రధాన పరిశోధకుడు (ట్రైనీ): DR. SAI CHARAN KULKARNI; గైడ్: ____________; సహ-గైడ్: ____________. సంప్రదించవలసిన నంబర్: ____________.

1. ఈ అధ్యయనం ఎందుకు చేస్తున్నారు? మీకు గుండెపోటు లేదా అస్థిర ఆంజైనా వచ్చి, గుండె రక్తనాళంలో స్టెంట్ వేయబడింది. మీరు రక్తాన్ని పలుచబరిచే (యాంటీప్లేట్‌లెట్) రెండు మందులు వాడాల్సి ఉంటుంది; వాటిలో ఒకటి తరచుగా క్లోపిడోగ్రెల్. CYP2C19 అనే జన్యువులో కొన్ని మార్పులు ఉన్నవారిలో శరీరం క్లోపిడోగ్రెల్‌ను సరిగా క్రియాశీల రూపంలోకి మార్చదు. మన రోగులలో ఈ మార్పులు ఎంత తరచుగా ఉన్నాయో, రాబోయే 90 రోజుల్లో రోగుల ఆరోగ్య స్థితి ఎలా ఉంటుందో తెలుసుకోవడమే ఈ అధ్యయనం లక్ష్యం.

2. నేను పాల్గొంటే ఏమి జరుగుతుంది? CYP2C19 జన్యు పరీక్ష మరియు ప్లేట్‌లెట్ పనితీరు పరీక్ష కోసం సిర నుండి సుమారు 5 మి.లీ. రక్తం తీసుకుంటారు. ఫలితాలు మీ వైద్యునికి అందుతాయి; మీ మందులు మార్చాలా వద్దా అనేది మీ వైద్యుడు మీతో చర్చించి నిర్ణయిస్తారు. మీ ఆసుపత్రి రికార్డుల నుండి సమాచారాన్ని నమోదు చేస్తాం, మరియు సుమారు 7, 30, 90 రోజులకు క్లినిక్ సందర్శన ద్వారా లేదా ఫోన్ ద్వారా మిమ్మల్ని సంప్రదిస్తాం. 12 నెలల వద్ద ఒకసారి మీ ఆరోగ్యం గురించి అడగవచ్చు.

3. ఏ జన్యువును పరీక్షిస్తారు? CYP2C19 జన్యువును మాత్రమే పరీక్షిస్తాం. క్లోపిడోగ్రెల్‌ను ప్రభావితం చేసే మార్పులను గుర్తించడానికి ఈ జన్యువులోని అన్ని ఎక్సాన్‌లను చదువుతాం (సీక్వెన్సింగ్). మీ పూర్తి జీనోమ్ లేదా ఎక్సోమ్‌ను సీక్వెన్స్ చేయం, ఇతర జన్యువులను పరిశీలించం, ఇతర వ్యాధుల గురించి సమాచారం వెతకం.

4. ప్రమాదాలు. రక్తం తీసేటప్పుడు కొద్దిసేపు అసౌకర్యం, చిన్న కమిలిన గుర్తు, అరుదుగా సిర వద్ద వాపు రావచ్చు. ఈ అధ్యయనం వల్ల ఇతర అదనపు ప్రమాదాలు లేవు.

5. ప్రయోజనాలు. మీకు నేరుగా ప్రయోజనం ఉండకపోవచ్చు. ఫలితం మీకు తగిన యాంటీప్లేట్‌లెట్ మందును ఎంచుకోవడంలో మీ వైద్యునికి సహాయపడవచ్చు. ఈ అధ్యయనం భవిష్యత్తులో ఇతర రోగులకు ఉపయోగపడవచ్చు.

6. ఖర్చులు. అధ్యయన పరీక్షలు మీకు ఉచితంగా చేయబడతాయి. పాల్గొన్నందుకు మీకు చెల్లింపు ఉండదు.

7. గోప్యత. ఏ నివేదికలోనూ మీ పేరు ఉండదు. మీ సమాచారం కోడ్ నంబర్‌తో నిల్వ చేయబడుతుంది; ఆ కోడ్ వివరాలు అధ్యయన బృందం వద్ద మాత్రమే ఉంటాయి (డిజిటల్ పర్సనల్ డేటా ప్రొటెక్షన్ చట్టం, 2023 ప్రకారం). మీ రక్త నమూనా ఈ అధ్యయనానికి మాత్రమే ఉపయోగించబడుతుంది, ఆ తరువాత ఎథిక్స్ కమిటీ ఆమోదించిన విధంగా నాశనం చేయబడుతుంది.

8. స్వచ్ఛంద భాగస్వామ్యం. కారణం చెప్పకుండా మీరు ఎప్పుడైనా నిరాకరించవచ్చు లేదా అధ్యయనం నుండి వైదొలగవచ్చు; దీని వల్ల మీ చికిత్సపై ఎలాంటి ప్రభావం ఉండదు.

9. ప్రశ్నలు. అధ్యయనానికి ముందు లేదా అధ్యయన సమయంలో మీరు ఏదైనా అడగవచ్చు. పైన పేర్కొన్న పరిశోధకుడిని లేదా ఇన్‌స్టిట్యూషనల్ ఎథిక్స్ కమిటీ సభ్య కార్యదర్శిని సంప్రదించండి: ____________.

Hindi version – Patient Information Sheet

अध्ययन का शीर्षक: एक्यूट कोरोनरी सिंड्रोम में जीनोटाइप-निर्देशित एंटीप्लेटलेट चिकित्सा: CYP2C19 जीनोटाइप, जोखिम कारक और 90 दिनों के परिणाम

शोधकर्ता: मुख्य शोधकर्ता (प्रशिक्षु): ____________; गाइड: ____________; सह-गाइड: ____________। संपर्क नंबर: ____________।

1. यह अध्ययन क्यों किया जा रहा है? आपको दिल का दौरा या अस्थिर एंजाइना हुआ है और आपके हृदय की रक्तवाहिनी में स्टेंट लगाया गया है। आपको रक्त को पतला करने वाली (एंटीप्लेटलेट) दो दवाएँ लेनी होंगी, जिनमें से एक अक्सर क्लोपिडोग्रेल होती है। CYP2C19 नामक जीन में कुछ बदलाव होने पर शरीर क्लोपिडोग्रेल को सही ढंग से सक्रिय रूप में नहीं बदल पाता। इस अध्ययन का उद्देश्य यह जानना है कि हमारे मरीज़ों में ये बदलाव कितने आम हैं और अगले 90 दिनों में मरीज़ों की स्थिति कैसी रहती है।

2. यदि मैं भाग लूँ तो क्या होगा? CYP2C19 जीन जाँच और प्लेटलेट कार्य जाँच के लिए नस से लगभग 5 मि.ली. रक्त लिया जाएगा। परिणाम आपके डॉक्टर को मिलेंगे और आपकी दवाएँ बदलनी हैं या नहीं, यह आपके डॉक्टर आपके साथ चर्चा करके तय करेंगे। हम आपकी अस्पताल फ़ाइल से जानकारी दर्ज करेंगे और लगभग 7, 30 और 90 दिन पर क्लिनिक में या फ़ोन पर आपसे संपर्क करेंगे। 12 महीने पर एक बार आपके स्वास्थ्य के बारे में पूछा जा सकता है।

3. कौन-सा जीन जाँचा जाएगा? केवल CYP2C19 जीन जाँचा जाएगा। क्लोपिडोग्रेल को प्रभावित करने वाले बदलावों को पहचानने के लिए इस जीन के सभी एक्सॉन पढ़े जाएँगे (सीक्वेंसिंग)। आपके पूरे जीनोम या एक्सोम की सीक्वेंसिंग नहीं की जाएगी, अन्य जीन नहीं देखे जाएँगे और अन्य बीमारियों की जानकारी नहीं खोजी जाएगी।

4. जोखिम. रक्त लेते समय थोड़ी देर असुविधा, हल्का नीला निशान या कभी-कभी नस के पास सूजन हो सकती है। इस अध्ययन से कोई अन्य अतिरिक्त जोखिम नहीं है।

5. लाभ. आपको सीधा लाभ नहीं भी हो सकता है। परिणाम आपके डॉक्टर को आपके लिए उपयुक्त एंटीप्लेटलेट दवा चुनने में मदद कर सकता है। यह अध्ययन भविष्य में अन्य मरीज़ों के काम आ सकता है।

6. खर्च. अध्ययन की जाँचें आपसे निःशुल्क की जाएँगी। भाग लेने के लिए आपको कोई भुगतान नहीं मिलेगा।

7. गोपनीयता. किसी भी रिपोर्ट में आपका नाम नहीं होगा। आपकी जानकारी कोड नंबर के साथ रखी जाएगी; कोड की कुंजी केवल अध्ययन दल के पास रहेगी (डिजिटल पर्सनल डेटा प्रोटेक्शन अधिनियम, 2023 के अनुसार)। आपका रक्त नमूना केवल इसी अध्ययन में उपयोग किया जाएगा और बाद में एथिक्स कमेटी की स्वीकृति के अनुसार नष्ट कर दिया जाएगा।

8. स्वैच्छिक भागीदारी. आप बिना कारण बताए कभी भी मना कर सकते हैं या अध्ययन से हट सकते हैं; इससे आपके इलाज पर कोई असर नहीं पड़ेगा।

9. प्रश्न. अध्ययन से पहले या उसके दौरान आप कुछ भी पूछ सकते हैं। ऊपर दिए गए शोधकर्ता से या संस्थागत एथिक्स कमेटी के सदस्य सचिव से संपर्क करें: ____________।

APPENDIX C: INFORMED CONSENT FORM

Study title: CYP2C19 Genotype, Risk Factors and 90-Day Outcomes of Genotype-Guided Antiplatelet Therapy in Acute Coronary Syndrome

Participant’s name / study ID: ______________________   Age/Sex: ______

Please initial each box.

Statement	Initials
I have read, or have had read to me in a language I understand, the Participant Information Sheet dated ______, and I have had the chance to ask questions.
I understand that taking part is voluntary and that I may withdraw at any time without my medical care or legal rights being affected.
I agree to give blood for CYP2C19 genetic testing (including sequencing of all exons of this gene) and a platelet function test, and I understand that only the CYP2C19 gene, which is related to clopidogrel, will be tested and no other gene will be examined.
I agree that my doctor may receive my test results and use them in my treatment.
I agree to be contacted at about 7, 30 and 90 days, and once at 12 months, and to the use of my hospital records for this study.
I understand that my identity will be kept confidential and that coded data may be published without my name.
I understand that my sample will be used only for this study and destroyed afterwards.

 

Person	Name	Signature / thumb impression	Date
Participant
Impartial witness (if participant is illiterate)
Investigator who took consent

Telugu version  - Informed Consent Form

అధ్యయన శీర్షిక: అక్యూట్ కరోనరీ సిండ్రోమ్‌లో జన్యు-ఆధారిత యాంటీప్లేట్‌లెట్ చికిత్స: CYP2C19 జన్యురూపం, ప్రమాద కారకాలు మరియు 90 రోజుల ఫలితాలు

పాల్గొనేవారి పేరు / అధ్యయన ID: ______________________   వయస్సు / లింగం: ______

దయచేసి ప్రతి పెట్టెలో మీ మొదటి అక్షరాలు వేయండి.

ప్రకటన	మొదటి అక్షరాలు
నేను పాల్గొనేవారి సమాచార పత్రాన్ని (తేదీ ______) చదివాను, లేదా నాకు అర్థమయ్యే భాషలో చదివి వినిపించారు; ప్రశ్నలు అడిగే అవకాశం నాకు లభించింది.
పాల్గొనడం స్వచ్ఛందమని, నా వైద్య సంరక్షణ లేదా చట్టపరమైన హక్కులపై ప్రభావం లేకుండా నేను ఎప్పుడైనా వైదొలగవచ్చని నాకు అర్థమైంది.
CYP2C19 జన్యు పరీక్ష (ఈ జన్యువులోని అన్ని ఎక్సాన్‌ల సీక్వెన్సింగ్‌తో సహా) మరియు ప్లేట్‌లెట్ పనితీరు పరీక్ష కోసం రక్తం ఇవ్వడానికి నేను అంగీకరిస్తున్నాను. క్లోపిడోగ్రెల్‌కు సంబంధించిన CYP2C19 జన్యువు మాత్రమే పరీక్షించబడుతుందని, ఇతర జన్యువులు పరీక్షించబడవని నాకు అర్థమైంది.
నా పరీక్ష ఫలితాలను నా వైద్యుడు అందుకుని, నా చికిత్సలో ఉపయోగించవచ్చని నేను అంగీకరిస్తున్నాను.
సుమారు 7, 30, 90 రోజులకు మరియు 12 నెలల వద్ద ఒకసారి నన్ను సంప్రదించడానికి, ఈ అధ్యయనం కోసం నా ఆసుపత్రి రికార్డులను ఉపయోగించడానికి నేను అంగీకరిస్తున్నాను.
నా గుర్తింపు గోప్యంగా ఉంటుందని, కోడ్ చేసిన సమాచారం నా పేరు లేకుండా ప్రచురించబడవచ్చని నాకు అర్థమైంది.
నా నమూనా ఈ అధ్యయనానికి మాత్రమే ఉపయోగించబడి, ఆ తరువాత నాశనం చేయబడుతుందని నాకు అర్థమైంది.

 

వ్యక్తి	పేరు	సంతకం / వేలిముద్ర	తేదీ
పాల్గొనేవారు
నిష్పక్షపాత సాక్షి (పాల్గొనేవారు నిరక్షరాస్యులైతే)
సమ్మతి తీసుకున్న పరిశోధకుడు

Hindi version  - Informed Consent Form

अध्ययन का शीर्षक: एक्यूट कोरोनरी सिंड्रोम में जीनोटाइप-निर्देशित एंटीप्लेटलेट चिकित्सा: CYP2C19 जीनोटाइप, जोखिम कारक और 90 दिनों के परिणाम

प्रतिभागी का नाम / अध्ययन ID: ______________________   आयु / लिंग: ______

कृपया प्रत्येक खाने में अपने आद्याक्षर लिखें।

कथन	आद्याक्षर
मैंने प्रतिभागी सूचना पत्र (दिनांक ______) पढ़ा है, या मुझे वह मेरी समझ की भाषा में पढ़कर सुनाया गया है, और मुझे प्रश्न पूछने का अवसर मिला है।
मैं समझता/समझती हूँ कि भाग लेना स्वैच्छिक है और मैं अपनी चिकित्सा देखभाल या कानूनी अधिकारों पर असर पड़े बिना कभी भी हट सकता/सकती हूँ।
मैं CYP2C19 जीन जाँच (इस जीन के सभी एक्सॉन की सीक्वेंसिंग सहित) और प्लेटलेट कार्य जाँच के लिए रक्त देने के लिए सहमत हूँ। मैं समझता/समझती हूँ कि केवल क्लोपिडोग्रेल से संबंधित CYP2C19 जीन की जाँच होगी और अन्य जीन नहीं जाँचे जाएँगे।
मैं सहमत हूँ कि मेरे डॉक्टर मेरे जाँच परिणाम प्राप्त करें और मेरे इलाज में उनका उपयोग करें।
मैं लगभग 7, 30 और 90 दिन पर तथा 12 महीने पर एक बार संपर्क किए जाने और इस अध्ययन के लिए मेरे अस्पताल के रिकॉर्ड के उपयोग के लिए सहमत हूँ।
मैं समझता/समझती हूँ कि मेरी पहचान गोपनीय रखी जाएगी और कोड की गई जानकारी मेरे नाम के बिना प्रकाशित की जा सकती है।
मैं समझता/समझती हूँ कि मेरा नमूना केवल इसी अध्ययन में उपयोग होगा और उसके बाद नष्ट कर दिया जाएगा।

 

व्यक्ति	नाम	हस्ताक्षर / अंगूठे का निशान	दिनांक
प्रतिभागी
निष्पक्ष गवाह (यदि प्रतिभागी निरक्षर हो)
सहमति लेने वाला शोधकर्ता

APPENDIX D: MASTER CHART - VARIABLE CODING SHEET

One row per participant in the Excel master chart; variables and codes are as below.

No.	Variable	Coding
1	Study ID	Serial number
2	Age	Years
3	Sex	1 = male, 2 = female
4	BMI	kg/m²; category 0 = <23, 1 = 23-24.9, 2 = ≥25
5	Diagnosis	1 = STEMI, 2 = NSTEMI, 3 = unstable angina
6	Type 2 diabetes mellitus	0 = no, 1 = yes
7	Hypertension	0 = no, 1 = yes
8	Hypercholesterolaemia	0 = no, 1 = yes
9	Chronic kidney disease	0 = no, 1 = yes
10	Smoking	0 = never, 1 = former, 2 = current
11	PPI use	0 = no, 1 = yes
12	Genotype by real-time PCR (diplotype)	Text, for example *1/*2
13	Other variants on exon sequencing	Text (exon, change, function)
14	CPIC phenotype	1 = UM, 2 = RM, 3 = NM, 4 = IM, 5 = PM, 6 = indeterminate
15	LOF carrier	0 = no, 1 = yes (any no-function allele); *2 / *3 carriage in separate columns
16	Platelet function result	Value in units of the assay used
17	HTPR	0 = below assay cut-off, 1 = at or above cut-off
18	P2Y12 inhibitor at discharge	1 = clopidogrel, 2 = ticagrelor, 3 = prasugrel
19	CPIC concordance	0 = discordant, 1 = concordant (blank if indeterminate)
20	MACE at day 7 / 30 / 90	0 = no, 1 = yes (three columns)
21	Component of first MACE	1 = death, 2 = MI, 3 = stroke, 4 = stent thrombosis
22	BARC bleeding (maximum type)	0 = none, 1, 2, 3a, 3b, 3c, 5
23	Unplanned readmission / revascularisation	0 = no, 1 = yes
24	Follow-up status	1 = complete, 2 = lost (date of last contact)

APPENDIX E: OPERATIONAL DEFINITIONS AND REFERENCE TABLES

E1. Outcome and variable definitions

Term	Definition
MACE (primary)	Composite of all-cause death, non-fatal myocardial infarction, ischaemic stroke, and definite or probable stent thrombosis within 90 days.
Myocardial infarction	Fourth Universal Definition of Myocardial Infarction (rise and/or fall of troponin with clinical evidence of ischaemia); spontaneous recurrent infarction after the index event.19
Stent thrombosis	Academic Research Consortium-2 definite or probable stent thrombosis (angiographic or pathological confirmation for definite; unexplained death or target-vessel infarction without angiography for probable).20
Bleeding	BARC type 1 (not requiring medical attention); 2 (overt, requiring non-surgical medical intervention, hospitalisation or evaluation); 3a (haemoglobin fall 3 to <5 g/dL); 3b (fall ≥5 g/dL, tamponade, surgery or vasoactive drugs); 3c (intracranial or intraocular); 5 (fatal).21
HTPR	High on-treatment platelet reactivity: result above the consensus cut-off for the assay used (for example, VASP platelet reactivity index above 50%).10
LOF carrier	Carrier of at least one no-function allele (*2, *3 and any other no-function allele in the CPIC allele function table); *2 and *3 carriage are also reported separately.8
Indeterminate phenotype	Diplotype containing one or two alleles of uncertain function; described separately and excluded from the concordance analysis.
Type 2 diabetes mellitus	Known diabetes on treatment, or HbA1c ≥6.5% on admission.
Chronic kidney disease	eGFR below 60 mL/min/1.73 m² (CKD-EPI) at admission with supporting history. [Guide to confirm.]
Hypercholesterolaemia	LDL-C ≥100 mg/dL on admission or on lipid-lowering therapy. [Guide to confirm.]
BMI categories	Normal below 23, overweight 23-24.9, obese ≥25 kg/m² (Asian-Indian cut-offs).
CPIC-concordant therapy	Intermediate or poor metabolisers on prasugrel or ticagrelor; normal, rapid or ultrarapid metabolisers on clopidogrel.8

E2. CYP2C19 diplotype, phenotype and CPIC 2022 recommendation (ACS / PCI)

Phenotype	Example diplotypes	Recommendation
Ultrarapid (UM)	*17/*17	Clopidogrel 75 mg daily if considered (strong)
Rapid (RM)	*1/*17	Clopidogrel 75 mg daily if considered (strong)
Normal (NM)	*1/*1	Clopidogrel 75 mg daily if considered (strong)
Intermediate (IM)	*1/*2, *1/*3, *2/*17, *3/*17	Avoid standard-dose clopidogrel if possible; prasugrel or ticagrelor at standard dose if no contraindication (strong)
Poor (PM)	*2/*2, *2/*3, *3/*3	Avoid clopidogrel if possible; prasugrel or ticagrelor at standard dose if no contraindication (strong)
Likely IM / likely PM	*1/*9, *9/*17 (likely IM); *2/*9, *3/*9 (likely PM)	Same as intermediate / poor, respectively (strong)
Indeterminate	*1/*12, *2/*12	No recommendation; excluded from concordance analysis

 

Source: Lee et al., CPIC guideline, 2022 update.8

E3. Sample size scenarios (prevalence formula, p = 0.46, Z = 1.96)

Absolute precision (d)	Calculated n	With 10% attrition	Decision
0.05	382	425	Not feasible in enrolment window
0.07	195	217	Selected
0.08	150	166	Fallback

APPENDIX F: STUDY TIMELINE

Months	Activity
1-2	IEC approval, finalisation of the case record form, staff training in blood collection and genotyping / platelet function sampling protocols, pilot of CRF
3-20	Active enrolment by consecutive sampling to reach 217 participants
3-23	Follow-up at 7, 30 and 90 days from each participant’s enrolment
21-24	Database lock, statistical analysis, thesis and manuscript writing

APPENDIX G: THESIS PROTOCOL APPROVAL (TPA) LETTER

(To be issued only on the official letterhead of the hospital; format as prescribed by NBEMS.)

Ref. No: ____________________

Date: ____________

Executive Director,

National Board of Examinations in Medical Sciences,

Medical Enclave, Ansari Nagar, Mahatma Gandhi Marg (Ring Road), New Delhi-110029

Subject: Thesis Protocol Approval Letter

Sir,

This is for your kind information that the research proposal/thesis protocols of the below-listed DNB candidates have been considered and reviewed by the Institutional Ethics Committee (IEC) in its meeting held on ________________.

S.N.	Name of DNB candidate	Specialty	Session	Roll No.	Thesis topic title
1	____________	Cardiology			CYP2C19 Genotype, Risk Factors and 90-Day Outcomes of Genotype-Guided Antiplatelet Therapy in Acute Coronary Syndrome
2

 

The IEC which reviewed the proposals is duly registered with the Department of Health Research (DHR), Ministry of Health & Family Welfare, Government of India. The authenticated copies of the composition of the IEC are enclosed herewith. The IEC has approved conducting the study on the above-listed research proposal(s) of DNB candidate(s) for the purpose of writing their DNB theses.

It is further certified that the proposed research protocol(s) have not been/shall not be submitted elsewhere for any degree, fellowship or any other titles for recognition. The minutes of the aforesaid meetings of the IEC are available with the hospital and can be reproduced before NBEMS, if so required, at any point of time.

 

 

Name & signature of the Academic Head/DNB Coordinator	Name & signature of the Administrative Head

 

Encl.: Composition of Institutional Ethics Committee (IEC)