Expert Opinion on Drug Metabolism & Toxicology最新文献

Introduction: Parkinson's disease is a chronic neurodegenerative multisystemic disorder that affects approximately 2% of the population over 65 years old. This disorder is characterized by motor symptoms which are frequently accompanied by non-motor symptoms such as cognitive disorders. Current drug therapies aim to reduce the symptoms and increase the patient's life expectancy. Nevertheless, there is heterogeneity in therapy response in terms of efficacy and adverse effects. This wide range in response may be linked to genetic variability. Thus, it has been suggested that pharmacogenomics may help to tailor and personalize drug therapy for Parkinson's disease.

Areas covered: This review describes and updates the clinical impact of genetic factors associated with the efficacy and adverse drug reactions related to common medications used to treat Parkinson's disease. Additionally, we highlight current informative recommendations for the drug treatment of Parkinson's disease.

Expert opinion: The pharmacokinetic, pharmacodynamic, and safety profiles of Parkinson's disease drugs do not favor the development of pharmacogenetic tests with a high probability of success. The chances of obtaining ground-breaking pharmacogenetics biomarkers for Parkinson's disease therapy are limited. Nevertheless, additional information on the metabolism of certain drugs, and an analysis of the potential of pharmacogenetics in novel drugs could be of interest.

Introduction: Atopic dermatitis (AD) is associated with reduced quality of life, depression, and anxiety, making efficacious and safe treatments a priority. We will focus on the safety, efficacy, and pharmacokinetics of JAK1 inhibitors used in the treatment of AD.

Areas covered: In this review, the pharmacodynamics, pharmacokinetics, safety, and efficacy of JAK1 inhibitors for the treatment of atopic dermatitis are discussed. The data was obtained by searching ClinicalTrials.gov, PubMed, and Google Scholar. Articles between January 2012 and March 2023 were considered for inclusion.

Expert opinion: Given the rare, but serious black box warnings with JAK inhibitors, patients and providers may be weary of initiating treatment. In these instances, clinicians may weigh the risks and benefits of treatment with this class. Risk is relative, and while there are risks to treating AD with JAK inhibitors, there are also risks to untreated or undertreated AD, including infection and impairments in mental, physical, and psychosocial function. While JAK1 inhibitors appear to be safe, they were only recently approved for AD in January 2022, and more long-term safety data is needed. We expect to see additional FDA approval of these drugs, new formulations, and more safety and efficacy data in the future.

Introduction: Perinatal asphyxia (PA) still causes significant morbidity and mortality. Therapeutic hypothermia (TH) is the only effective therapy for neonates with moderate to severe hypoxic-ischemic encephalopathy after PA. These neonates need additional pharmacotherapy, and both PA and TH may impact physiology and, consequently, pharmacokinetics (PK) and pharmacodynamics (PD).

Areas covered: This review provides an overview of the available knowledge in PubMed (until November 2022) on the pathophysiology of neonates with PA/TH. In vivo pig models for this setting enable distinguishing the effect of PA versus TH on PK and translating this effect to human neonates. Available asphyxia pig models and methodological considerations are described. A summary of human neonatal PK of supportive pharmacotherapy to improve neurodevelopmental outcomes is provided.

Expert opinion: To support drug development for this population, knowledge from clinical observations (PK data, real-world data on physiology), preclinical (in vitro and in vivo (minipig)) data, and molecular and cellular biology insights can be integrated into a predictive physiologically-based PK (PBPK) framework, as illustrated by the I-PREDICT project (Innovative physiology-based pharmacokinetic model to predict drug exposure in neonates undergoing cooling therapy). Current knowledge, challenges, and expert opinion on the future directions of this research topic are provided.

Background: Givinostat (ITF2357), an oral, synthetic histone deacetylase inhibitor, significantly improved all histological muscle biopsy parameters in a Phase II study in boys with Duchenne muscular dystrophy (DMD).

Research design and methods: A population pharmacokinetic (PK) model, including seven clinical studies, was developed to explore the effect of covariates on givinostat PK. The final model was qualified to simulate pediatric dosing recommendations. A PK/pharmacodynamic (PD) model was developed to simulate the link between givinostat plasma concentration and platelet time course in 10-70-kg children following 6 months of givinostat 20-70 mg twice daily.

Results: A two-compartment model, with first-order input with lag and first-order elimination from the central compartment, described givinostat PK, demonstrating increasing apparent clearance with increasing body weight. The PK/PD model well-described platelet count time course. Weight-based dosing (arithmetic mean systemic exposure of 554-641 ng·h/mL) produced an average platelet count decrease from baseline of 45% with maximum decrease within 28 days. After 1 week and 6 months, ~1% and ~14-15% of patients, respectively, had a platelet count <75 × 10⁹/L.

Conclusions: Based on these data, givinostat dosing will be body weight adjusted and include monitoring of platelet counts to support efficacy and safety in a Phase III DMD study.

Introduction: Long-acting injectable (LAI) formulations of second-generation antipsychotics (SGA) are a mainstay in the treatment of schizophrenia-spectrum patients, and their use improves adherence and reduces relapse risk. Personalizing LAI-based therapy involves tailoring the transition from oral to LAIs based on individual and drug-related pharmacokinetic peculiarities.

Areas covered: We discuss pharmacokinetic considerations as a cornerstone of a smooth transition from oral to LAI SGAs based on works identified using an updated search in PubMed and Embase in February 2023. Establishing the extent of antipsychotic exposure during oral SGA-treatment from the patient's SGA levels is often a more appropriate orientation method to choose the equivalent LAI dose than population-based data. Oral dose adjustment during LAI transition can also be guided by checking SGA levels before the LAI injection.

Expert opinion: LAI SGAs may dominate the maintenance treatment of schizophrenia-spectrum disorders with increased use for other severe mental illnesses such as bipolar disorder. Spurring this trend is the development of newer formulations with longer injection intervals and increased administration ease, but transitioning from oral SGA remains a challenge. By understanding the pharmacokinetics of LAI formulations and measuring SGA levels during oral therapy, one can personalize/optimize the switch from oral SGAs to LAI counterparts.

Objectives: The objective of this study was to monitor and identify adverse events (AEs) associated with topotecan, a medication used for the treatment of solid tumors, in order to improve patient safety and guide medication usage.

Methods: To assess the disproportionality of topotecan-related AEs in real-world data, four algorithms (ROR, PRR, BCPNN, and EBGM) were employed as measures to detect signals of topotecan-associated AEs.

Results: A statistical analysis was conducted using data from the FAERS database, encompassing 9,511,161 case reports from 2004Q1 to 2021Q4. Among these reports, 1,896 were identified as primary suspected (PS) AEs related to topotecan, and 155 topotecan-related adverse drug reactions (ADRs) at the preferred terms (PTs) level were selected. The occurrence of topotecan-induced ADRs was analyzed across 23 organ systems. The analysis revealed several expected ADRs, such as anemia, nausea, and vomiting, which were consistent with the drug labels. Additionally, unexpected significant ADRs associated with eye disorders at the system organ class (SOC) level were identified, indicating potential adverse effects not currently mentioned in the drug instructions.

Conclusion: This study identified new and unexpected signals of adverse drug reactions (ADRs) related to topotecan, providing valuable insights into the relationship between ADRs and topotecan usage. The findings highlight the importance of ongoing monitoring and surveillance to detect and manage AEs effectively, ultimately improving patient safety during topotecan treatment.

Background: Insulin detemir (IDet) is an insulin analog used to treat diabetes. IDet shows full efficacy but reduced potency compared to human insulin (HI) in both man and rat. In contrast, in pigs and dogs, IDet appears to have full in vivo potency. Non-receptor mediated degradation (NRMD) has previously been suggested as an explanation for the low potency of IDet, but this hypothesis has not been investigated further until now. Bacitracin is a nonspecific protease inhibitor which we hypothesized could inhibit NRMD of IDet in rats.

Research design and methods: Healthy male rats instrumented with permanent catheters underwent euglycemic clamp during constant infusion of either HI or IDet at effect-matched doses with co-infusion of vehicle or bacitracin.

Results: Plasma concentrations of IDet increased significantly (p < 0.005) during bacitracin compared to vehicle co-infusion and the concomitant increase in glucose infusion rate (GIR, p < 0.001) required to maintain euglycemic clamp indicates that the IDet rescued from NRMD indeed was active. No significant differences were detected with co-infusions of HI with either bacitracin or vehicle.

Conclusions: A large proportion of NRMD of IDet which can be inhibited by bacitracin may partly explain the reduced potency of IDet observed in rats and likely also in man.