The evolving role of investigative toxicology in the pharmaceutical industry.

For decades, preclinical toxicology was essentially a descriptive discipline in which treatment-related effects were carefully reported and used as a basis to calculate safety margins for drug candidates. In recent years, however, technological advances have increasingly enabled researchers to gain insights into toxicity mechanisms, supporting greater understanding of species relevance and translatability to humans, prediction of safety events, mitigation of side effects and development of safety biomarkers. Consequently, investigative (or mechanistic) toxicology has been gaining momentum and is now a key capability in the pharmaceutical industry.

Arthroscopic repair of inferior glenoid labrum tears (Down Under lesions) produces similar outcomes to other glenoid tears.

Purpose: Inferior glenoid labral tears are an uncommon but distinct shoulder injury. Only a small number of studies have reported outcomes following arthroscopic repair. The aim of the current study was to report minimum 2-year outcomes following inferior labral repair and to compare outcomes and risk factors associated with the injury to non-inferior labral tears.

Is there a role for the no observed adverse effect level in safety pharmacology?

In nonclinical toxicology the highest dose or exposure without test article-related adverse effects, known as the No Observed Adverse Effect Level (NOAEL), is a variable that may be determined. In safety pharmacology the vast majority of the endpoints measured are quantitative numeric functional endpoints such as changes in heart rate, blood pressure or respiratory frequency, endpoints that are usually not assessed using a defined framework of adversity. Therefore, we asked the question: is there a role for the NOAEL in safety pharmacology? To help answer this question, we conducted a survey via the Safety Pharmacology Society.

Optimizing drug discovery by Investigative Toxicology: Current and future trends.

Investigative Toxicology describes the de-risking and mechanistic elucidation of toxicities, supporting early safety decisions in the pharmaceutical industry. Recently, Investigative Toxicology has contributed to a shift in pharmaceutical toxicology, from a descriptive to an evidence-based, mechanistic discipline. This was triggered by high costs and low throughput of Good Laboratory Practice in vivo studies, and increasing demands for adhering to the 3R (Replacement, Reduction and Refinement) principles of animal welfare.

An overview of the safety pharmacology society strategic plan.

Safety Pharmacology studies are conducted to characterize the confidence by which biologically active new chemical entities (NCE) may be anticipated as safe. Non-clinical safety pharmacology studies aim to detect and characterize potentially undesirable pharmacodynamic activities using an array of in silico, in vitro and in vivo animal models. While a broad spectrum of methodological innovation and advancement of the science occurs within the Safety Pharmacology Society, the society also focuses on partnerships with health authorities and technology providers and facilitates interaction with organizations of common interest such as pharmacology, physiology, neuroscience, cardiology and toxicology.

Novel selective PDE type 1 inhibitors cause vasodilatation and lower blood pressure in rats.

Background And Purpose: The PDE enzymes (PDE1-11) hydrolyse and thus inactivate cyclic nucleotides and are important in the regulation of the cardiovascular system. Here,we have investigated the effects on the cardiovascular system, of two novel selective PDE1 inhibitors, Lu AF41228 and Lu AF58027.

Experimental Approach: We used rat mesenteric small arteries (internal diameters of 200-300 μm), RT-PCR and measured isometric wall tension.

The Benefits of Streamlined Hip Fracture Management in a Regional Hospital.

Introduction: Hip fracture is an increasingly common injury in the growing elderly population. The morbidity and mortality associated with this injury can be reduced by minimizing delays to surgical treatment. We describe the impact of a regional hospital service redesign project that utilized the principles of smart simplicity, a management strategy that lays emphasis on collaboration to achieve desired goals.

Ion currents of cardiomyocytes in different regions of the Göttingen minipig heart.

Introduction: The Göttingen minipig is a promising model for pharmacological safety assessment and for translational research in cardiology. We have examined the main ion currents in cardiomyocytes of the minipig heart.

Methods: Cardiac cells were isolated from different cardiac regions (endo-, mid- and epicardial left ventricle and right ventricle) from Göttingen minipigs and examined using the whole cell patch clamp technique combined with pharmacological interventions.

Patients presenting with fractures are likely to be vitamin D deficient: are we getting enough sun?

Background: 25-Hydroxyvitamin D serves a crucial role in bone metabolism through its role on osteoclast and osteoblastic function. To assess the implication of vitamin D and its relationship to bone fracture and fracture force, we have examined vitamin D levels in patients requiring inpatient fracture management.

Methods: We performed serological testing of vitamin D levels, calcium, parathyroid hormone and liver function tests on patients admitted to our rural institution in southeastern Australia for inpatient fracture management.

Assessment of anti-arrhythmic activity of antipsychotic drugs in an animal model: influence of non-cardiac α₁-adrenergic receptors.

Torsades de Pointes (TdP) is a potentially lethal cardiac arrhythmia and a known adverse effect of many drugs secondary to block of the rapidly activating delayed rectifier potassium current (IKr). In animal models antipsychotic drugs have shown reduced pro-arrhythmic potential compared to drugs with comparable IKr-blocking characteristics. The reduced pro-arrhythmic properties of antipsychotic drugs has been attributed to a variety of different causes e.

Validation of a high throughput flow cytometric in vitro micronucleus assay including assessment of metabolic activation in TK6 cells.

Genotoxicity is an unacceptable property for new drug candidates and we employ three screening assays during the drug discovery process to identify genotoxicity early and optimize chemical series. One of these methods is the flow cytometric in vitro micronucleus assay for which protocol optimizations have been described recently. Here, we report further validation of the assay in TK6 cells including assessment of metabolic activation.

High-content analysis/screening for predictive toxicology: application to hepatotoxicity and genotoxicity.

High-content imaging/analysis has emerged as a powerful tool for predictive toxicology as it can be used for identifying and mitigating potential safety risks during drug discovery. By careful selection of end-points, some cellular assays can show better predictivity than routine animal toxicity testing for certain adverse events. Here, we present the perhaps most utilized high-content screening assays for predictive toxicology in the pharmaceutical industry.

Exploratory toxicology as an integrated part of drug discovery. Part II: Screening strategies.

In an effort to reduce toxicity-related attrition, different strategies have been implemented throughout the pharmaceutical industry. Previously (in Part I), we have outlined our 'integrated toxicology' strategy, which aims to provide timely go/no-go decisions (fail early) but also to show a direction to the drug discovery teams (showing what will not fail). In this review (Part II of the series) we describe our compound testing strategies with respect to cardiovascular safety, hepatotoxicity, genotoxicity, immunotoxicity and exploratory in vivo toxicity.

Exploratory toxicology as an integrated part of drug discovery. Part I: Why and how.

Toxicity and clinical safety have major impact on drug development success. Moving toxicological studies into earlier phases of the R&D chain prevents drug candidates with a safety risk from entering clinical development. However, to identify candidates without such risk, safety has to be designed actively.

A high content screening assay to predict human drug-induced liver injury during drug discovery.

Introduction: Adverse drug reactions are a major cause for failures of drug development programs, drug withdrawals and use restrictions. Early hazard identification and diligent risk avoidance strategies are therefore essential. For drug-induced liver injury (DILI), this is difficult using conventional safety testing.

Keeping the rhythm -- pro-arrhythmic investigations in isolated Göttingen minipig hearts.

Introduction: Cardiac arrhythmia is a potentially lethal condition. A better prediction and mechanistic understanding of human cardiac arrhythmia is dependent on the development of good animal models. Minipigs are increasingly being used in cardiovascular research and we hypothesize that Langendorff-perfused minipig hearts could serve as a novel model of pro-arrhythmia.

Characterization of cardiac repolarization in the Göttingen minipig.

Introduction: The minipig represents an attractive experimental animal within cardiovascular research due to its extensive similarities to the human heart in terms of anatomy and physiology. Although minipigs have been used for cardiovascular research for decades no thorough characterization of the minipig cardiac electrophysiology has been performed. Therefore, we have for the first time characterized the minipig cardiac repolarization in a series of experiments ranging from mRNA quantification to in vivo studies.

Orthostatic hypotensive effect of antipsychotic drugs in Wistar rats by in vivo and in vitro studies of alpha1-adrenoceptor function.

Rationale: Many antipsychotics cause orthostatic hypotension possibly due to antagonist action on resistance vessel alpha1A-adrenoceptors (alpha1A-AR).

Objective: We have tested this possibility by determining in Wistar rats how the orthostatic hypotensive effect of several antipsychotic drugs compares with their affinity for adrenoceptors in mesenteric small arteries (MSA with mainly alpha1A-AR) and aorta (mainly alpha1D-AR).

Materials And Methods: Using a tilt setup, orthostatic hypotension was measured in anaesthetized rats for prazosin and the antipsychotics haloperidol, sertindole, risperidone, clozapine, ziprasidone, domperidone, olanzapine, and aripiprazole.

Chronic treatment with antipsychotics in rats as a model for antipsychotic-induced weight gain in human.

Several clinical reports have demonstrated that most antipsychotics of the new generation, but not the typical antipsychotic haloperidol, induce weight gain in schizophrenic patients. Since weight gain induces serious health complications in humans, it is crucial to test upcoming antipsychotic compounds in an animal model of weight gain. With the aim of evaluating whether the rat can be used as a model for antipsychotic-induced weight gain, we have investigated the effect of chronic treatment (3 weeks) with one antipsychotic drug inducing weight gain in clinic (olanzapine) and one antipsychotic not inducing weight gain in clinic (haloperidol), on food and water intake and body weight gain in rats.

No expression of angiotensin II receptors and angiotensin-converting enzyme in myxomatous canine mitral valve leaflets. An autoradiographic study.

The renin-angiotensin system, including angiotensin (Ang) II and angiotensin-converting enzyme (ACE), plays an important role in cardiac fibrous tissue formation. Since changes in valvular collagen are a central part of myxomatous mitral valve disease in the dog, we speculated that Ang II and ACE might play a role in the pathogenesis of this disease. In 10 mitral valves, five with and five without clear myxomatous changes, the presence and distribution of Ang II receptors and ACE was examined autoradiographically, using 125I-Ang II and 125I-lisinopril, respectively.

Heart rate variability in young, clinically healthy Dachshunds: influence of sex, mitral valve prolapse status, sampling period and time of day.

Objective: This study investigatest the influence of sampling period duration, time of day, age, sex, body weight and degree of mitral valve prolapse (MVP) on various measures of heart rate variability (HRV) in the dog. The correlations between the HRV parameters were also investigated.

Background: Holter recording is increasingly being used in dogs but method studies are sparse.