prasugrel-hydrochloride and Body-Weight

The 3 main clinical manifestations of acute coronary syndrome (ACS) are unstable angina, non-ST-segment myocardial infarction, and ST-segment myocardial infarction. Together they comprise a major cause of emergency care and hospitalization in the United States. Consequently, all hospital-based physicians should be familiar with current recommendations regarding the diagnosis and management of ACS. Effective inhibition of platelet activation and aggregation is central to the treatment of ACS, and dual antiplatelet therapy with aspirin and a P2Y12 inhibitor is recommended in all patients with ACS. Recently, the American Heart Association and American College of Cardiology Foundation published focused updates to their guidelines for the management of ACS patients. These updates included changes in antiplatelet therapy arising from the introduction of prasugrel and ticagrelor as alternatives to clopidogrel for the P2Y12 inhibitor component of dual antiplatelet therapy. Among the P2Y12 inhibitors recommended for each indication, the guidelines do not advocate any one P2Y12 inhibitor over another, but instead recommend that therapy is individualized based on each patient's demographic and clinical characteristics. This article presents a clinical case study to illustrate the hospital management of ST-segment myocardial infarction and unstable angina/non-ST-segment myocardial infarction with particular reference to the latest changes in antiplatelet therapy guidelines. This article outlines key differences in the indications and recommendations for P2Y12 inhibitors and summarizes clinical data from the pivotal studies of prasugrel and ticagrelor.

Topics: Acute Coronary Syndrome; Adenosine; Age Factors; Aspirin; Body Weight; Clopidogrel; Humans; Myocardial Infarction; Piperazines; Platelet Aggregation Inhibitors; Practice Guidelines as Topic; Prasugrel Hydrochloride; Quality of Health Care; Randomized Controlled Trials as Topic; Thiophenes; Ticagrelor; Ticlopidine

The safety of prasugrel in elderly and/or low body weight Japanese patients with ischemic stroke who have a relatively high bleeding risk with antiplatelet therapy remains unknown.. We aimed to investigate the safety and efficacy of long-term prasugrel monotherapy for stroke prevention compared with clopidogrel in elderly and/or low body weight Japanese patients with non-cardioembolic ischemic stroke.. In this randomized, double-blind, comparative, phase III study, elderly (age ≥75 years) and/or low body weight (≤50 kg) Japanese patients with a previous history of non-cardioembolic ischemic stroke were assigned to a prasugrel 3.75 mg (PRA3.75) group, a prasugrel 2.5 mg (PRA2.5) group, or a clopidogrel 50 mg (CLO50) group and followed up for 48 weeks. The primary safety endpoint was the combined incidence of primary safety events, defined as life-threatening, major, and other clinically relevant bleeding. The efficacy endpoint was a composite of ischemic stroke, myocardial infarction, and death from other vascular causes.. A total of 654 patients (age 76.4 ± 7.3 years, body weight 55.6 ± 9.3 kg, women 43.9%) from 74 medical institutions within Japan were enrolled. The combined incidence (95% CI) of primary safety events was 4.2% (1.9-7.8%), 1.9% (0.5-4.7%), and 3.6% (1.6-6.9%) in the PRA3.75 group (n = 216), PRA2.5 group (n = 215), and CLO50 group (n = 223), respectively (hazard ratios [HR] PRA3.75/CLO50, 1.13 [0.44-2.93]; PRA2.5/CLO50, 0.51 [0.15-1.69]). The incidences of bleeding leading to treatment discontinuation (95% CI) were 2.3% (0.8-5.3%), 0.9% (0.1-3.3%), and 2.2% (0.7-5.2%) in the PRA3.75, PRA2.5, and CLO50 groups, respectively (HRs PRA3.75/CLO50, 1.01 [0.29-3.48]; PRA2.5/CLO50, 0.41 [0.08-2.12]). There was no significant difference in all bleeding events between groups. The incidence of ischemic stroke, myocardial infarction, and death from other vascular causes was lower, but not significantly so, in patients treated with prasugrel than in patients treated with clopidogrel: PRA3.75, 0.0% (0/216); PRA2.5, 3.3% (7/215); and CLO50, 3.6% (8/223; HRs PRA3.75/CLO50, 0.00 [0.00-0.00]; PRA2.5/CLO50, 0.90 [0.32-2.47]).. Elderly and/or low body weight -Japanese patients with previous non-cardioembolic ischemic stroke who received PRA3.75 showed similar results in terms of primary safety endpoint, and a numerically lower incidence of ischemic stroke, myocardial infarction, and death from other vascular causes, compared with those who received CLO50.

Topics: Age Factors; Aged; Aged, 80 and over; Asian People; Body Weight; Brain Ischemia; Clopidogrel; Double-Blind Method; Female; Health Status; Hemorrhage; Humans; Incidence; Japan; Male; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Recurrence; Risk Assessment; Risk Factors; Stroke; Time Factors; Treatment Outcome

The efficacy and safety of a reduced dose of prasugrel versus a standard dose of ticagrelor in elderly patients or those with a low body weight presenting with an acute coronary syndrome (ACS) are unknown.. To investigate the effect of an age- and weight-adapted dose of prasugrel versus a standard dose of ticagrelor in patients with ACS. (ClinicalTrials.gov: NCT01944800).. Prespecified analysis of the multicenter, randomized ISAR-REACT 5 trial.. 23 centers in Germany and Italy.. 3997 patients with ACS planned for invasive management.. Participants were randomly assigned to receive a standard dose of ticagrelor or prasugrel (reduced dose in the elderly or low-weight group and standard dose in the neither elderly nor low-weight group).. The efficacy end point was a composite of death, myocardial infarction, or stroke, and the safety end point was bleeding, both at 12 months.. In the elderly or low-weight group, the efficacy end point occurred in 12.7% of patients assigned to receive prasugrel and 14.6% of those assigned to receive ticagrelor (hazard ratio [HR], 0.82 [95% CI, 0.60 to 1.14]); in the neither elderly nor low-weight group, the efficacy end point occurred in 4.8% of patients assigned to receive prasugrel and 7.3% of those assigned to receive ticagrelor (HR, 0.65 [CI, 0.48 to 0.88];. The study is a subgroup analysis.. In elderly or low-weight patients with ACS, a reduced dose of prasugrel compared with the standard dose of ticagrelor is associated with maintained anti-ischemic efficacy while protecting these patients against the excess risk for bleeding.. German Center for Cardiovascular Research and Deutsches Herzzentrum München.

Topics: Acute Coronary Syndrome; Age Factors; Aged; Body Weight; Drug Dosage Calculations; Female; Hemorrhage; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Ticagrelor; Treatment Outcome

In TRITON-TIMI 38, levels of the prasugrel active metabolite (pras-AM) were measured in a population pharmacokinetic substudy that characterized the intrinsic and extrinsic factors influencing exposure. Higher exposure to the pras-AM was observed in low-weight or very elderly patients. The authors hypothesized that this higher exposure might explain the higher risk of non-coronary artery bypass graft (CABG)-related TIMI-related bleeding observed in these 2 patient populations. The relationship between estimated exposure to the pras-AM and clinical outcomes was assessed in 1159 prasugrel-treated patients enrolled in the substudy using multivariable logistic regression analysis. There was no relationship between pras-AM exposure and efficacy through 3 days or after 3 days. Higher estimated pras-AM exposure was associated with a higher incidence of non-CABG-related TIMI major or minor bleeding after 3 days (P < .05) but not through 3 days from start of study drug. Factors associated with increased risk for non-CABG-related TIMI bleeding (≥75 years and <60 kg) also identified subgroups with higher exposure to the pras-AM. Within low body weight and very elderly subgroups, bleeding was largely confined to patients having the highest exposure to the pras-AM, indicating that a prasugrel lower dose in these subgroups may reduce the risk of bleeding while maintaining efficacy.

Topics: Acute Coronary Syndrome; Age Factors; Aged; Biotransformation; Body Weight; Dose-Response Relationship, Drug; Double-Blind Method; Hemorrhage; Humans; Incidence; Male; Models, Biological; Piperazines; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Prodrugs; Purinergic P2Y Receptor Antagonists; Receptors, Purinergic P2Y12; Severity of Illness Index; Thiophenes; Thrombosis

The relationship of platelet function testing measurements with outcomes in patients with acute coronary syndromes (ACS) initially managed medically without revascularization is unknown.. To characterize the differences and evaluate clinical outcomes associated with platelet reactivity among patients with ACS treated with clopidogrel or prasugrel.. Patients with medically managed unstable angina or non-ST-segment elevation myocardial infarction were enrolled in the TRILOGY ACS trial (2008 to 2011) comparing clopidogrel vs prasugrel. Of 9326 participants, 27.5% were included in a platelet function substudy: 1286 treated with prasugrel and 1278 treated with clopidogrel.. Aspirin with either prasugrel (10 or 5 mg/d) or clopidogrel (75 mg/d); those 75 years or older and younger than 75 years but who weighed less than 60 kg received a 5-mg prasugrel maintenance dose.. Platelet reactivity, measured in P2Y12 reaction units (PRUs), was performed at baseline, at 2 hours, and at 1, 3, 6, 12, 18, 24, and 30 months after randomization. The primary efficacy end point was a composite of cardiovascular death, myocardial infarction, or stroke through 30 months.. Among participants younger than 75 years and weighing 60 kg or more, the median PRU values at 30 days were 64 (interquartile range [IQR], 33-128) in the prasugrel group vs 200 (IQR, 141-260) in the clopidogrel group (P < .001), a difference that persisted through all subsequent time points. For participants younger than 75 years and weighing less than 60 kg, the median 30-day PRU values were 139 (IQR, 86-203) for the prasugrel group vs 209 (IQR, 148-283) for the clopidogrel group (P < .001), and for participants 75 years or older, the median PRU values were 164 (IQR, 105-216) for the prasugrel group vs 222 (IQR, 148-268) for the clopidogrel group (P < .001). At 30 months the rate of the primary efficacy end point was 17.2% (160 events) in the prasugrel group vs 18.9% (180 events) in the clopidogrel group (P = .29). There were no significant differences in the continuous distributions of 30-day PRU values for participants with a primary efficacy end point event after 30 days (n = 214) compared with participants without an event (n = 1794; P = .07) and no significant relationship between the occurence of the primary efficacy end point and continuous PRU values (adjusted hazard ratio [HR] for increase of 60 PRUs, 1.03; 95% CI, 0.96-1.11; P = .44). Similar findings were observed with 30-day PRU cut points used to define high on-treatment platelet reactivity-PRU more than 208 (adjusted HR, 1.16; 95% CI, 0.89-1.52, P = .28) and PRU more than 230 (adjusted HR, 1.20; 95% CI, 0.90-1.61; P = .21).. Among patients with ACS without ST-segment elevation and initially managed without revascularization, prasugrel was associated with lower platelet reactivity than clopidogrel, irrespective of age, weight, and dose. Among those in the platelet substudy, no significant differences existed between prasugrel vs clopidogrel in the occurence of the primary efficacy end point through 30 months and no significant association existed between platelet reactivity and occurrence of ischemic outcomes.. clinicaltrials.gov Identifier: NCT00699998.

Topics: Acute Coronary Syndrome; Age Factors; Aged; Angina, Unstable; Aspirin; Body Weight; Clopidogrel; Female; Humans; Male; Myocardial Infarction; Myocardial Ischemia; Piperazines; Platelet Activation; Platelet Aggregation Inhibitors; Platelet Function Tests; Prasugrel Hydrochloride; Stroke; Thiophenes; Ticlopidine; Treatment Outcome

An integrated analysis of pharmacokinetic (PK) parameter estimates for prasugrel, from 16 phase I clinical pharmacology studies, consolidated exposure estimates from 506 healthy male and female participants and evaluated the effect of specific intrinsic and extrinsic factors on exposure to prasugrel's active metabolite (AM, R-138727). A linear mixed effect model was fitted with study and subject nested within study as random effects and subject factors as fixed effects. Prasugrel AM exposure was similar in males and females, in participants <65 years and ≥65 years, in smokers and nonsmokers, in drinkers and nondrinkers of alcohol, and in Asians, Caucasians, and participants of African and Hispanic descent. Prasugrel AM exposure increased as body weight decreased and was 40% higher in participants <60 kg than in participants ≥60 kg. Exposure in Asians was 40% higher than that in Caucasians, but this difference could be explained by the lower overall weight of the Asian participants and a disproportionately large difference between ethnic groups in lighter participants, especially those <60 kg. These results characterize prasugrel's PK across a range of studies and highlight body weight as the most influential covariate on prasugrel AM exposure, with implications for prasugrel maintenance dosing in clinical practice.

Topics: Acute Coronary Syndrome; Adolescent; Adult; Aged; Aged, 80 and over; Biotransformation; Body Weight; Female; Half-Life; Humans; Male; Middle Aged; Models, Biological; Piperazines; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Prodrugs; Purinergic P2Y Receptor Antagonists; Receptors, Purinergic P2Y12; Thiophenes; Young Adult

Due to concern about bleeding complications, a maintenance dose of prasugrel 2.5 mg may be used in elderly or low-body-weight patients in Japan. There is little information, however, on the efficacy and safety of a 2.5-mg maintenance dose of prasugrel. Methods and Results: In this single-center, prospective, open-label, cross-over study, a total of 44 elderly (≥75 years old) or low body-weight (<50 kg) Japanese patients >1 month after percutaneous coronary intervention who were treated with aspirin 81-100 mg and clopidogrel 75 mg were randomized to either prasugrel 2.5 mg or 3.75 mg instead of clopidogrel for 14 days, with a cross-over directly to the alternate treatment for another 14 days. Platelet inhibition was assessed with the VerifyNow assay (Accumetrics, San Diego, CA, USA) at 3 time points: baseline; day 14; and day 28. P2Y12 reaction units (PRU) ≤95 was defined as low on-treatment platelet reactivity (LPR), and PRU ≥262 as high on-treatment platelet reactivity (HPR). The prevalence of LPR was 2.2% in patients treated with clopidogrel, 2.2% in those with prasugrel 2.5 mg, and 22.7% in those with prasugrel 3.75 mg (P<0.001). Clopidogrel resulted in the higher prevalence of HPR compared with 2.5-mg and 3.75-mg prasugrel (40.9% vs. 18.2% vs. 6.8%, P<0.001).. Prasugrel 2.5 mg may be more appropriate in elderly or lower-body-weight Japanese patients.

Topics: Aged; Aged, 80 and over; Body Weight; Cross-Over Studies; Female; Humans; Japan; Male; Percutaneous Coronary Intervention; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Count; Prasugrel Hydrochloride; Prospective Studies; Treatment Outcome

The current standard of antiplatelet therapy for patients with myocardial infarction (MI) includes the P2Y12-receptor antagonist clopidogrel, prasugrel or ticagrelor. While it has been shown that platelet reactivity after clopidogrel administration depends on factors such as body weight, it is not known if these factors have an effect on the activity of prasugrel or ticagrelor. Thus, this study aimed to analyse factors associated with high residual platelet reactivity after administration of third generation P2Y12-antagonists compared to clopidogrel. In a single centre registry the antiplatelet effect of clopidogrel, prasugrel or ticagrelor was investigated by aggregometry in patients after MI. To assess the overall capacity of platelet aggregation whole blood was induced with thrombin receptor activating peptide (TRAP; 32 µM). To specifically quantify the effect of P2Y12-antagonists, blood was stimulated with 6.4 µM adenosine diphophosphate (ADP). Relative ADP induced aggregation (r-ADP-agg) was defined as the ADP-TRAP-ratio to reflect an individual degree of P2Y12-dependent platelet inhibition. Platelet function of 238 patients was analysed [clopidogrel (n = 58), prasugrel (n = 65), ticagrelor (n = 115)]. It was found that the r-ADP-agg correlated significantly with body weight in patients after clopidogrel administration (r = 0.423; p < 0.001). In contrast, this association was not present in patients after prasugrel (r = -0.117; p = 0.354) or ticagrelor (r = -0.082; p = 0.382) administration. Comparison of the correlation coefficients showed a significant difference (p = 0.003). In contrast to clopidogrel, platelet reactivity after administration of prasugrel or ticagrelor does not depend on body weight in patients after MI. Hence, our mechanistic data support the results of large clinical trials indicating that patients with high body weight do not need to be treated with increased doses of third generation P2Y12-antagonists to achieve sufficient platelet inhibition (registry for patients after myocardial infarction treated with antiplatelet agents; DRKS00003146).

Topics: Adenosine; Body Weight; Clopidogrel; Dose-Response Relationship, Drug; Drug Dosage Calculations; Humans; Platelet Activation; Platelet Aggregation; Prasugrel Hydrochloride; Purinergic P2Y Receptor Antagonists; Ticagrelor; Ticlopidine

Patients treated with clopidogrel who have higher body size exhibit greater platelet reactivity than patients with lower body size. In a retrospective analysis of the FEATHER trial, we examined the relationship between platelet response to thienopyridines clopidogrel 75 mg (Clop-75), prasugrel 5mg (Pras-5), and prasugrel 10mg (Pras-10) using 3 body size indices: body weight (BW), body mass index (BMI), and body surface area (BSA). Relationships were assessed as continuous variables and as 4 incremental body size groups.. Aspirin-treated patients with stable coronary artery disease (N=72) and a BW range of 45-134 kg received Clop-75, Pras-5, and Pras-10 in a 3-period, blinded, cross-over study. Platelet assays included maximum platelet aggregation (MPA) to 20μM ADP by light transmission aggregometry, VerifyNow-P2Y12 reaction units (PRU), and vasodilator-associated stimulated phosphoprotein (VASP) phosphorylation platelet reactivity index (PRI). Exposure to active metabolites (AMs) was also assessed.. Body size was a determinant of AM exposure and residual platelet reactivity regardless of type and dose of thienopyridine. BW and BSA demonstrated marginally stronger correlations with platelet reactivity; VASP-PRI demonstrated a stronger correlation with the body size than the other tests. Correlation coefficients ranged from a high of 0.64 (BW vs. PRI on Pras-5) to a low of 0.34 (BMI vs. MPA on Pras-10), but all were statistically significant (p<0.01).. Using a comprehensive selection of body size indices, AM exposures, platelet function tests, and thienopyridine doses, we demonstrated a consistent inverse relationship between body size and response to clopidogrel and prasugrel.

Topics: Adult; Aged; Biomarkers; Blood Platelets; Body Mass Index; Body Size; Body Surface Area; Body Weight; Cell Adhesion Molecules; Clopidogrel; Coronary Artery Disease; Drug Dosage Calculations; Female; Humans; Male; Microfilament Proteins; Middle Aged; Phosphoproteins; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Function Tests; Prasugrel Hydrochloride; Purinergic P2Y Receptor Antagonists; Randomized Controlled Trials as Topic; Receptors, Purinergic P2Y12; Retrospective Studies; Ticlopidine; Treatment Outcome

The aim of this study was to confirm prior modeling data suggesting that prasugrel 5 mg in low-body-weight (LBW) patients would be noninferior to prasugrel 10 mg in higher-body-weight (HBW) patients as assessed by maximal platelet aggregation (MPA).. Prasugrel 10 mg reduced ischemic events compared with clopidogrel 75 mg but increased bleeding, particularly in LBW patients.. In this blinded, 3-period, crossover study in stable patients with coronary artery disease (CAD) taking aspirin, prasugrel 5 and 10 mg and clopidogrel 75 mg were administered to LBW (56.4 ± 3.7 kg; n = 34) and HBW patients (84.7 ± 14.9 kg; n = 38). Assays included light transmission aggregometry (LTA), VerifyNow P2Y12 (VN), and vasodilator-associated stimulated phosphoprotein (VASP) level measured predose and after each 12-day treatment.. Median MPA by LTA for prasugrel 5 mg in LBW patients was noninferior to the 75th percentile for prasugrel 10 mg in HBW patients (primary endpoint) and mean MPA was similar, but active metabolite exposure was lowered by 38%. Within LBW patients, prasugrel 5 mg lowered MPA more than clopidogrel (least squares mean difference [95% confidence interval]: -3.7% [-6.72%, -0.69%]) and resulted in lower rates of high on-treatment platelet reactivity (HPR). Within HBW patients, prasugrel 10 mg lowered MPA more than clopidogrel (-16.9% [-22.3%, -11.5%]). Similar results were observed by VN and VASP. Prasugrel 10 mg in LBW patients was associated with more mild to moderate bleeding (mainly bruising) compared with prasugrel 5 mg and clopidogrel.. In aspirin-treated patients with CAD, prasugrel 5 mg in LBW patients reduced platelet reactivity to a similar extent as prasugrel 10 mg in HBW patients and resulted in greater platelet inhibition, lower HPR, and similar bleeding rates compared with clopidogrel. (Comparison of Prasugrel and Clopidogrel in Low Body Weight Versus Higher Body Weight With Coronary Artery Disease [FEATHER]; NCT01107925).

Topics: Adolescent; Adult; Aged; Blood Platelets; Body Weight; Clopidogrel; Coronary Artery Disease; Cross-Over Studies; Female; Humans; Male; Middle Aged; Piperazines; Platelet Aggregation; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Single-Blind Method; Thiophenes; Ticlopidine; Young Adult

Serial pharmacokinetic (PK) sampling in 1159 patients from TRITON-TIMI 38 was undertaken. A multilinear regression model was used to quantitatively predict prasugrel's active metabolite (Pras-AM) concentrations from its 2 downstream inactive metabolites. Population-based methods were then applied to Pras-AM concentration data to characterize the PK. The potential influence of body weight, body mass index, age, sex, renal function, diabetes, tobacco use, and other disease status on Bayesian estimates of Pras-AM exposures was assessed. The PK of Pras-AM was adequately described by a multicompartmental model and consistent with results from previous studies. The systemic exposure of prasugrel was not appreciably affected by body mass index, gender, diabetes, smoking, and renal impairment. Pras-AM mean exposure in patients weighing <60 kg (4.1%) was 30% (90% confidence interval [CI] 1.16-1.45) higher than exposure in patients > or =60 kg. Mean Pras-AM exposures for patients > or =75 years (10.5%) were 19% (90% CI: 1.11-1.28) higher compared with patients <75 years.

Topics: Adult; Age Factors; Aged; Aged, 80 and over; Body Weight; Clinical Trials, Phase III as Topic; Female; Humans; Linear Models; Male; Middle Aged; Models, Biological; Piperazines; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Prodrugs; Randomized Controlled Trials as Topic; Thiophenes