INSPIRE: A European training network to foster research and training in cardiovascular safety pharmacology

Short-Term Proteasome Inhibition: Assessment of the Effects of Carfilzomib and Bortezomib on Cardiac Function, Arterial Stiffness, and Vascular Reactivity

Proteasome inhibitors such as bortezomib and carfilzomib induce apoptosis and are a cornerstone in the treatment of relapsed or refractory multiple myeloma. However, concerns have emerged concerning their link to cancer therapy-related cardiovascular dysfunction (CTRCD). Bortezomib, a reversible first-generation inhibitor, and carfilzomib, a second-generation irreversible inhibitor, are associated with hypertension, heart failure, and cardiac arrhythmias. The current study investigated the effects of bortezomib and carfilzomib on cardiac (left ventricular ejection fraction, LVEF) and vascular (arterial stiffness, vascular reactivity) function. Cardiac function assessment aimed to build upon existing evidence of proteasome inhibitors CTRCD, while arterial stiffness served as an early indicator of potential vascular remodeling. Groups of 12-week-old C57BL/6J male mice (n = 8 per group) were randomly assigned to receive vehicle, carfilzomib (8 mg/kg I.P.), or bortezomib (0.5 mg/kg I.P.). Additionally, proteasome inhibition was assessed in mice treated with L-NAME (0.5 mg/kg) to induce hypertension. Cardiac and vascular parameters were evaluated via echocardiography on days 0 and 3. On day 6, mice were sacrificed for ex vivo analysis of arterial stiffness and vascular reactivity. Overall, no changes in arterial stiffness were detected either in vivo or ex vivo at basal pressures. However, a steeper pressure-stiffness curve was observed for carfilzomib in normotensive (p < 0.01) and hypertensive (p < 0.0001) mice ex vivo. Additionally, in hypertensive mice, carfilzomib decreased LVEF (p = 0.06), with bortezomib exhibiting similar trends. Vascular reactivity remained largely unchanged, but proteasome inhibition tended to enhance endothelial-independent relaxations in both control and hypertensive mice. In conclusion, short-term treatment with carfilzomib and bortezomib is considered relatively safe for the protocols assessed in the study.

"Appraisal of state-of-the-art" The 2021 Distinguished Service Award of the Safety Pharmacology Society: Reflecting on the past to tackle challenges ahead

This appraisal of state-of-the-art manuscript highlights and expands upon the thoughts conveyed in the lecture of Dr. Jean-Pierre Valentin, recipient of the 2021 Distinguished Service Award of the Safety Pharmacology Society, given on the 2nd December 2021. The article reflects on the strengths, weaknesses, opportunities, and threats that surrounded the evolution of safety and secondary pharmacology over the last 3 decades with a particular emphasis on pharmaceutical drug development delivery, scientific and technological innovation, complexities of regulatory framework and people leadership and development. The article further built on learnings from past experiences to tackle constantly emerging issues and evolving landscape whilst being cognizant of the challenges facing these disciplines in the broader drug development and societal context.

Optimization of bioanalysis of dried blood samples

INTRODUCTION

Pharmacokinetic/pharmacodynamic modelling has emerged as a valuable technique for understanding drug exposure and response relationships in drug development. Pharmacokinetic data are often obtained by taking multiple blood samples, which may disturb physiological parameters and complicate study designs. Wearable automatic blood sampling systems can improve this limitation by collecting dried blood samples at programmable time points without disrupting cardiovascular parameters. It is the objective of this study to evaluate the bioanalysis of DBS in comparison to conventional blood sampling techniques and to optimize the recovery of various compounds spiked into canine blood dried on filter paper tape.

METHODS

Incubated blood samples from Beagle dogs were spiked with 16 different compounds and half of the whole blood sample was centrifuged to obtain plasma. After the dried blood sample drops were dried, liquid chromatography-mass spectrometry methods were used to analyze the samples. The study explored different anticoagulants, sample preparation methods and technical approaches to best determine the compound concentrations in dried blood samples.

RESULTS

With the two anticoagulants tested and using the optimized sample preparation methods and technical approaches we employed, the bioanalysis of dried blood samples can provide equivalent results to conventional blood sampling techniques.

DISCUSSION

Automated blood sampling systems have the potential to provide increased numbers of blood samples, providing substantially more Pharmacokinetic data within safety pharmacology studies without disrupting physiological parameters. They can provide a viable alternative to traditional methods of obtaining blood for various other types of studies or analyses.

The impact of environmental and biological factors on the resting heart rate of dogs as assessed using 20 years of data from safety pharmacology studies

INTRODUCTION

A safety pharmacology study detects and evaluates potential side effects of a new drug on physiological function at therapeutic levels and above and, in most cases, prior to the initiation of clinical trials. The aim of this study was to investigate the effects of environmental and biological factors on resting heart rate (HR), a representative cardiac parameter in cardiovascular safety pharmacology.

METHODS

Over twenty years, 143 dogs (Beagles, Labradors and mongrels) received implanted telemetry transmitters to measure aortic pressure (AP), left ventricular pressure (LVP), Electrocardiogram (ECG) and body temperature. Throughout the 7-h period of data collection, data were continuously recorded without drug treatment and included the range of HRs resulting from spontaneous physiological changes. Statistics and visualizations were calculated using R and Spotfire.

RESULTS

Beagles had a higher HR than the mongrels, while Labradors had a lower HR than mongrels. Labradors were found to have a sex-based difference in HR, with females having a higher HR. A higher HR was observed in young animals of all breeds when they were in contact with humans. The cage system affected the HR of Labradors and mongrels more than Beagles. Larger dogs (e.g. Labrador) have a lower HR than smaller dogs (Beagles). Animals that are younger were found to have more HR variability and have a higher HR than older animals. In addition, older animals reacted less to the application period and human interaction than younger animals. The HR response of animals inside a cage system may depend on the cage system in which they were bred. A familiar cage system typically has less impact on HR.

DISCUSSION

This retrospective data base evaluation has demonstrated the impact of environmental and biological factors on cardiovascular parameters in the context of performing safety pharmacology studies. Breed, sex, age and the type of cage system used affected, at least in some cases, the HR and its variability. They should therefore be carefully considered when designing safety pharmacology studies to have the highest possible test sensitivity.

Use of new approach methodologies (NAMs) to meet regulatory requirements for the assessment of tobacco and other nicotine-containing products

Regulatory frameworks on tobacco and other nicotine-containing products (TNCP) continue to evolve as novel products emerge, including electronic nicotine delivery systems (e.g., electronic cigarettes or vaping products), heated tobacco products, or certain smokeless products (e.g., nicotine pouches). This article focuses on selected regulations for TNCPs that do not make health claims, and on the opportunities to use new approach methodologies (NAMs) to meet regulatory requirements for toxicological information. The manuscript presents a brief overview of regulations and examples of feedback from regulatory agencies whilst highlighting NAMs that have been successfully applied, or could be used, in a regulatory setting, either as stand-alone methods or as part of a weight-of-evidence approach to address selected endpoints. The authors highlight the need for agencies and stakeholders to collaborate and communicate on the development and application of NAMs to address specific regulatory toxicological endpoints. Collaboration across sectors and geographies will facilitate harmonized use of robust testing approaches to evaluate TNCPs without animal testing.