Pharmacokinetic Modeling of Morphine's Effect on Plasma Concentrations of Ticagrelor and Its Metabolite in Healthy Volunteers

Understanding Drug Interactions in Antiplatelet Therapy for Atherosclerotic Vascular Disease: A Systematic Review

BACKGROUND

Antiplatelet drugs are a cornerstone in managing atherosclerotic vascular disease (ASVD). However, their interactions with other medications present significant challenges to treatment efficacy and safety. Patients with ASVD often require multiple treatment regimens due to complex comorbidities, which increases the risk of drug-drug interactions (DDIs). These interactions can lead to drug resistance, reduced therapeutic outcomes, or adverse effects. A thorough understanding of DDIs is crucial for optimizing patient care.

AIMS

This review aims to explore the clinical significance. mechanisms, and implications of DDIs in antiplatelet therapy Additionally, it seeks to identify future research directions to advance personalized treatment strategies and improve therapeutic outcomes.

MATERIALS AND METHODS

A systematic literature review was conducted using key databases, focusing on clinical studies, mechanistic research, and guidelines related to antiplatelet therapy and DDIs. Findings were analyzed to identify common interaction patterns, associated risks, and management strategies.

RESULTS

The review identifies common DDIs involving antiplatelet drugs, particularly with anticoagulants, nonsteroidal anti-inflammatory drugs, and proton pump inhibitors. These interactions primarily occur through pharmacokinetic mechanisms, such as alterations in drug metabolism via cytochrome P450 enzymes, and pharmacodynamic mechanisms, including synergistic or antagonistic effects on platelet inhibition. Clinically, DDIs can increase bleeding risk, reduce antiplatelet efficacy, and contribute to adverse cardiovascular outcomes. Strategies to mitigate these risks include individualized drug selection, dose adjustments, genetic testing, and therapeutic drug monitoring.

DISCUSSION

Effective management of DDIs in antiplatelet therapy is essential to improve clinical outcomes. A patient-specific approach, considering comorbidities, genetic predispositions, and concurrent medications, is crucial. The review categorizes DDIs based on clinical settings and underscores the need for further research on predictive biomarkers, pharmacogenomics, and advanced monitoring techniques.

CONCLUSION

DDIs significantly impact the effectiveness and safety of antiplatelet therapy, necessitating a comprehensive understanding of their mechanisms and clinical implications. Future research should focus on developing personalized treatment approaches, integrating genetic testing, and optimizing pharmacological monitoring to minimize risks and improve therapeutic outcomes. This review provides a foundation for advancing clinical practice and enhancing the management of patients with ASVD.

Evaluating the pharmacokinetic and pharmacodynamic impact of different modes of ticagrelor administration

INTRODUCTION

Alternative administration modes for oral P2Y12 inhibitors, particularly ticagrelor, have emerged as a potential alternative to overcome the limitations associated with the delayed onset of action of these drugs in patients who are unable to swallow or with impaired absorption.

AREAS COVERED

This comprehensive literature review aims to provide an overview of the current state of knowledge on the pharmacokinetics and administration modes of ticagrelor, including factors that may affect its action. It also compares the pharmacokinetics of ticagrelor with that of other drugs with similar uses to provide a comprehensive understanding of the potential advantages and limitations of different modalities of P2Y12 administration. For this purpose, Embase, Medline, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, Google Scholar, and ClinicalTrials.gov were searched from database inception to July 2023.

EXPERT OPINION

Among the different alternatives, crushed formulations, especially for ticagrelor, have emerged as the most promising option, showing early and robust platelet inhibition. However, important questions remain unanswered, such as the comparative clinical benefits of crushed ticagrelor versus standard administration, the cost-effectiveness of alternative modes compared to intravenous P2Y12 inhibitors such as cangrelor, and the important limitations associated with the concomitant use of opioids, who have been proven to impair even the action of crushed ticagrelor.

Negative Impact of ST-Segment Elevation Myocardial Infarction and Morphine Dose on Ticagrelor Uptake and Pharmacodynamics: A Population PK/PD Analysis of Pooled Individual Participant Data

BACKGROUND

Ticagrelor is widely used in patients with stable and acute coronary artery disease. Understanding the factors that influence its pharmacokinetics (PK) and pharmacodynamics (PD) could improve therapeutic outcomes. We therefore performed a pooled population PK/PD analysis using individual patient data from two studies. We focused on the impact of morphine administration and ST-segment elevation myocardial infarction (STEMI) on the risk of high platelet reactivity (HPR) and dyspnea.

METHODS

A parent-metabolite population PK/PD model was developed based on data from 63 STEMI, 50 non-STEMI, and 25 chronic coronary syndrome (CCS) patients. Simulations were then run to evaluate the risk of non-response and adverse events associated with the identified variability factors.

RESULTS

The final PK model consisted of first-order absorption with transit compartments, distribution with two compartments for ticagrelor and one compartment for AR-C124910XX (active metabolite of ticagrelor), and linear elimination for both drugs. The final PK/PD model was an indirect turnover model with production inhibition. Morphine dose and STEMI, independently, had a significant negative effect on the absorption rate (reduction of log([Formula: see text]) by 0.21×morphine dose (mg) and by 2.37 in STEMI patients, both p < 0.001), and the presence of STEMI significantly impacted both efficacy and potency (both p < 0.001). The simulations run with the validated model showed a high rate of non-response in patients with those covariates (RR 1.19 for morphine, 4.11 for STEMI and 5.73 for morphine and STEMI, all three p < 0.001). By increasing ticagrelor dosage, the negative morphine effect was reversible in patients without STEMI and just limited in patients with STEMI.

CONCLUSION

The developed population PK/PD model confirmed the negative impact of morphine administration and presence of STEMI on ticagrelor PK and antiplatelet effect. Increasing ticagrelor doses seems effective in morphine users without STEMI, whereas the STEMI effect is not entirely reversible.

Endogenous opiates and behavior: 2021

This paper is the forty-fourth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2021 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonizts and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).