Youth Suicide: A Population Crying for Help? A System Overloaded? Who Can Help?

Suicide is the second leading cause of death in young adults (15-24 years old). There continues to be limited access to mental health services for many patients who are in mental health crisis because of shortage of trained psychiatrist and mental health providers. Patients identified with high risk factors should get a full comprehensive psychiatric evaluation. Management should focus on preventative strategies, early identification as well as treatment with appropriate psychopharmacology and psychotherapy.

Cardiac voltage-gated ion channels in safety pharmacology: Review of the landscape leading to the CiPA initiative

Voltage gated ion channels are central in defining the fundamental properties of the ventricular cardiac action potential (AP), and are also involved in the development of drug-induced arrhythmias. Many drugs can inhibit cardiac ion currents, including the Na⁺ current (I_Na), L-type Ca²⁺ current (Ica-L), and K⁺ currents (I_to, I_K1, I_Ks, and I_Kr), and thereby affect AP properties in a manner that can trigger or sustain cardiac arrhythmias. Since publication of ICH E14 and S7B over a decade ago, there has been a focus on drug effects on QT prolongation clinically, and on the rapidly activating delayed rectifier current (I_Kr), nonclinically, for evaluation of proarrhythmic risk. This focus on QT interval prolongation and a single ionic current likely impacted negatively some drugs that lack proarrhythmic liability in humans. To rectify this issue, the Comprehensive in vitro proarrhythmia assay (CiPA) initiative has been proposed to integrate drug effects on multiple cardiac ionic currents with in silico modelling of human ventricular action potentials, and in vitro data obtained from human stem cell-derived ventricular cardiomyocytes to estimate proarrhythmic risk of new drugs with improved accuracy. In this review, we present the physiological functions and the molecular basis of major cardiac ion channels that contribute to the ventricle AP, and discuss the CiPA paradigm in drug development.

Motivation and competence of participants in a learner-centered student-run clinic: an exploratory pilot study

BACKGROUND

The Learner-Centered Student-run Clinic (LC-SRC) was designed to teach and train prescribing skills grounded in a real-life context, to provide students with early clinical experience and responsibility. The current studies' theoretical framework was based on the Self-determination Theory. According to the Self-determination Theory, early involvement in clinical practice combined with a high level of responsibility makes the LC-SRC an environment that can stimulate intrinsic motivation. We investigated the different types of motivation and the proficiency in CanMEDS competencies of the participating students.

METHOD

Type of motivation was measured using the Academic Motivation Scale and Intrinsic Motivation Inventory. CanMEDS competencies were evaluated by faculty using a mini-clinical examination and by the students themselves using a post-participation questionnaire.

RESULTS

The 29 participating students were highly intrinsic motivated for this project on all subscales of the Intrinsic Motivation Inventory. Motivation for medical school on the Academic Motivation Scale was high before and was not significantly changed after participation. Students considered that their CanMEDS competencies "Collaborator", "Communicator", "Academic", and "Medical expert" had improved. Their actual clinical team competence was judged by faculty to be at a junior doctor level.

CONCLUSION

Students showed a high level of intrinsic motivation to participate in the LC-SRC and perceived an improvement in competence. Furthermore their actual clinical competence was at junior doctor level in all CanMEDS competencies. The stimulating characteristics of the LC-SRC, the high levels of intrinsic motivation and the qualitative comments of the students in this study makes the LC-SRC an attractive place for learning.

Investigation of Elemental Mass Spectrometry in Pharmacology for Peptide Quantitation at Femtomolar Levels

In the search of new robust and environmental-friendly analytical methods able to answer quantitative issues in pharmacology, we explore liquid chromatography (LC) associated with elemental mass spectrometry (ICP-MS) to monitor peptides in such complex biological matrices. The novelty is to use mass spectrometry to replace radiolabelling and radioactivity measurements, which represent up-to now the gold standard to measure organic compound concentrations in life science. As a proof of concept, we choose the vasopressin (AVP)/V1A receptor system for model pharmacological assays. The capacity of ICP-MS to provide highly sensitive quantitation of metallic and hetero elements, whatever the sample medium, prompted us to investigate this technique in combination with appropriate labelling of the peptide of interest. Selenium, that is scarcely present in biological media, was selected as a good compromise between ICP-MS response, covalent tagging ability using conventional sulfur chemistry and peptide detection specificity. Applying selenium monitoring by elemental mass spectrometry in pharmacology is challenging due to the very high salt content and organic material complexity of the samples that produces polyatomic aggregates and thus potentially mass interferences with selenium detection. Hyphenation with a chromatographic separation was found compulsory. Noteworthy, we aimed to develop a straightforward quantitative protocol that can be performed in any laboratory equipped with a standard macrobore LC-ICP-MS system, in order to avoid time-consuming sample treatment or special implementation of instrumental set-up, while allowing efficient suppression of all mass interferences to reach the targeted sensitivity. Significantly, a quantification limit of 57 ng Se L^-1 (72 femtomoles of injected Se) was achieved, the samples issued from the pharmacological assays being directly introduced into the LC-ICP-MS system. The established method was successfully validated and applied to the measurement of the vasopressin ligand affinity for its V1A receptor through the determination of the dissociation constant (Kd) which was compared to the one recorded with conventional radioactivity assays.

Recalibration of nonclinical safety pharmacology assessment to anticipate evolving regulatory expectations

Safety pharmacology (SP) has evolved in terms of architecture and content since the inception of the SP Society (SPS). SP was initially focused on the issue of drug-induced QT prolongation, but has now become a broad spectrum discipline with expanding expectations for evaluation of drug adverse effect liability in all organ systems, not merely the narrow consideration of torsades de pointes (TdP) liability testing. An important part of the evolution of SP has been the elaboration of architecture for interrogation of non-clinical models in terms of model development, model validation and model implementation. While SP has been defined by mandatory cardiovascular, central nervous system (CNS) and respiratory system studies ever since the core battery was elaborated, it also involves evaluation of drug effects on other physiological systems. The current state of SP evolution is the incorporation of emerging new technologies in a wide range of non-clinical drug safety testing models. This will refine the SP process, while potentially expanding the core battery. The continued refinement of automated technologies (e.g., automated patch clamp systems) is enhancing the scope for detection of adverse effect liability (i.e., for more than just IKr blockade), while introducing a potential for speed and accuracy in cardiovascular and CNS SP by providing rapid, high throughput ion channel screening methods for implementation in early drug development. A variety of CNS liability assays, which exploit isolated brain tissue, and in vitro electrophysiological techniques, have provided an additional level of complimentary preclinical safety screens aimed at establishing the seizurogenic potential and risk for memory dysfunction of new chemical entities (NCEs). As with previous editorials that preface the annual themed issue on SP methods published in the Journal of Pharmacological and Toxicological Methods (JPTM), we highlight here the content derived from the most recent (2015) SPS meeting held in Prague, Czech Republic. This issue of JPTM continues the tradition of providing a publication summary of articles primarily presented at the SPS meeting with direct bearing on the discipline of SP. Novel method development and refinement in all areas of the discipline are reflected in the content.

Comparing Drug-Disease Associations in Clinical Practice Guideline Recommendations and Drug Product Label Indications

Clinical practice guidelines (CPGs) and structured product labels (SPLs) are both intended to promote evidence-based medical practices and guide clinicians' prescribing decisions. However, it is unclear how well CPG recommendations about pharmacologic therapies for certain diseases match SPL indications for recommended drugs. In this study, we use publicly available data and text mining methods to examine drug-disease associations in CPG recommendations and SPL treatment indications for 15 common chronic conditions. Preliminary results suggest that there is a mismatch between guideline-recommended pharmacologic therapies and SPL indications. Conflicting or inconsistent recommendations and indications may complicate clinical decision making and implementation or measurement of best practices.

Guidelines for reporting experiments involving animals: the ARRIVE guidelines

British Journal of Pharmacology (BJP) is pleased to publish a new set of guidelines for reporting research involving animals, simultaneously with several other journals; the 'ARRIVE' guidelines (Animals in Research: Reporting In Vivo Experiments). This editorial summarizes the background to the guidelines, gives our view of their significance, considers aspects of specific relevance to pharmacology, re-states BJP's guidelines for authors on animal experiments and indicates our commitment to carrying on discussion of this important topic. We also invite feedback via the British Pharmacological Society website.

Benefits of the maximum tolerated dose (MTD) and maximum tolerated concentration (MTC) concept in aquatic toxicology

There is increasing recognition of the need to identify specific sublethal effects of chemicals, such as reproductive toxicity, and specific modes of actions of the chemicals, such as interference with the endocrine system. To achieve these aims requires criteria which provide a basis to interpret study findings so as to separate these specific toxicities and modes of action from not only acute lethality per se but also from severe inanition and malaise that non-specifically compromise reproductive capacity and the response of endocrine endpoints. Mammalian toxicologists have recognized that very high dose levels are sometimes required to elicit both specific adverse effects and present the potential of non-specific "systemic toxicity". Mammalian toxicologists have developed the concept of a maximum tolerated dose (MTD) beyond which a specific toxicity or action cannot be attributed to a test substance due to the compromised state of the organism. Ecotoxicologists are now confronted by a similar challenge and must develop an analogous concept of a MTD and the respective criteria. As examples of this conundrum, we note recent developments in efforts to validate protocols for fish reproductive toxicity and endocrine screens (e.g. some chemicals originally selected as 'negatives' elicited decreases in fecundity or changes in endpoints intended to be biomarkers for endocrine modes of action). Unless analogous criteria can be developed, the potentially confounding effects of systemic toxicity may then undermine the reliable assessment of specific reproductive effects or biomarkers such as vitellogenin or spiggin. The same issue confronts other areas of aquatic toxicology (e.g., genotoxicity) and the use of aquatic animals for preclinical assessments of drugs (e.g., use of zebrafish for drug safety assessment). We propose that there are benefits to adopting the concept of an MTD for toxicology and pharmacology studies using fish and other aquatic organisms and the development of sound criteria for data interpretation when the exposure of organisms has exceeded the MTD. While the MTD approach is well established for oral, topical, inhalational or injection exposure routes in mammalian toxicology, we propose that for exposure of aquatic organisms via immersion, the term Maximum Tolerated Concentration (MTC) is more appropriate.

Using pharmacokinetic/pharmacodynamic modelling in safety pharmacology to better define safety margins: a regional workshop of the Safety Pharmacology Society

This meeting was convened to encourage the incorporation of empirical and mechanism-based pharmacokinetic/pharmacodynamic (PK/PD) modelling into safety pharmacology to improve the predictability of nonclinical investigations for human outcomes. These technologies make use of mathematical expressions relating measured variables to derive essential parameters for describing responses and predicting the behaviour of biological systems to a drug. Hence, empirical PK/PD modelling is intended to define the in vivo interrelationship between three basic entities: time; drug concentrations; and drug effects. The most widely applied equation relating drug bioresponses to plasma concentrations is the Hill sigmoidal E(max) model, which allows the calculation of drug potency (EC(50)) and intrinsic activity (E(max)). However, since the latter parameters depend on attributes of the drug and on the biological system itself, this approach can fail to accurately foretell drug concentration-effect behaviour, particularly between species. A particular phenomenon of PK/PD analysis is hysteresis, which refers to the delay of the bioresponse time-course with respect to exposure time-course, as this provides valuable information on the direct or indirect nature of the drug mechanism of action. The application of these concepts to the examination of the QT interval prolongation produced by dofetilide was discussed. A development surmounting the limitations of empirical PK/PD models is mechanism-based PK/PD modelling because its toolkits integrate specific mathematical expressions replicating the drug (e.g., affinity, intrinsic efficacy), and the physiological system (e.g., nonlinear, time-dependent, transduction processes), properties that play a crucial role in the cascade of biological events culminating in bioresponses. The usefulness of this approach was illustrated by a thorough analysis of nonclinical respiratory depressant and antinociceptive data on buprenorphine and fentanyl for successfully predicting the human safety and efficacy of these analgesic agents. Thus, PK/PD models can be viewed as in silico clones of drug and biological system activities that provide high-level knowledge that can avoid inappropriate attrition, and hasten the progress, of novel drugs, along the entire critical path of pharmaceutical development.

Identifying and validating novel targets with in vivo disease models: guidelines for study design

In vivo studies are an important tool for the identification and validation of novel drug targets in medicine; however, the interpretation of submitted and published data is often compromised by inadequate study design. Different study protocols, including the number of control groups and group size calculations, differ in target identification and validation studies. Furthermore, animal studies require that the selected target or compound meets the requirements for species specificity and target specificity; thus, providing the rationale for the selection of a particular species, strain, gender and age of the animals is necessary. Altogether, the presentation of target validation studies should meet defined criteria similar to those used in human trials.

Perception of risk of adverse drug reactions by medical students: influence of a 1 year pharmacological course

AIMS

To investigate how adverse drug reactions (ADRs) to several classes of drugs are perceived by young medical students before and after a 1 year pharmacology course.

METHODS

The whole cohort of 92 medical students (63 females and 29 males) was questioned during their third year. A visual analogue scale was used to define a score (ranging from 0 to 10) of perceived risk of ADRs associated with each drug class before and at the end of the pharmacological training period.

RESULTS

Before the pharmacology course, hypnotics were ranked as the most dangerous drugs by the medical students, followed by antidepressants and anticoagulants. Contraceptive pills were listed in the last position. After pharmacological training, antidepressants moved into the first position, followed by anticoagulants and hypnotics. When all different drug classes were taken as a whole, the mean (+/-SD) of median scores of the perceived risk were 4.8 (+/-1.3) before and 5.8 (+/-1.5) at the end of the pharmacology course (P < 0.0001). Except for antidiabetics, antihypertensive drugs, tranquillizers, corticosteroids and hypnotics, the perceived risk significantly increased after the pharmacology course for the other drugs. The highest increases were observed for contraceptive pills (+104%, P < 0.01), NSAIDs (+86%, P < 0.01) and aspirin (+56%, P < 0.01).

CONCLUSIONS

Pharmacological training allows young medical students to be aware of potentially serious ADRs associated with drugs, in particular with drugs considered relatively safe (such as NSAIDs and aspirin) by nonhealth professionals.

Adaptation of the Application of Good Clinical Practice Depending on the Features of Specific Research Projects

The conduct of clinical trials falls within a strict regulatory framework. The objective of the round table was to develop reasonable recommendations for the implementation of GCP according to the type of research and taking in account the risks and challenges related to this research. Two types of risks have been identified: those related to the characteristics of the research and those related to the impact of the study results. The group designed an evaluation table of these risks. The round table focused its investigations on 3 main themes: monitoring, the investigational medicinal product and undesirable effects. Three methods of monitoring adaptation were analysed in terms of advantages and disadvantages: the gradual approach, the central monitoring, monitoring on the basis of sampling. Examination of the investigational medicinal product focused on the medicinal product circuit. The group recommends using the following 'basic' decision-making tree, which takes three elements into account: 1) is it an investigational medicinal product?, 2) do the trial objectives and design require packaging specific to the research?, 3) is the risk of use higher than that in standard practice? Finally, adaptation of the implementation of GCP in terms of pharmacovigilance appeared very limited and could possibly be considered for the medicinal product, the subject of the research, which already holds a marketing authorisation, and for which the safety profile is well known; in this case, only simplified collection of non-serious adverse events may be envisaged, which may be implemented by designing and using a standard collection listing. The adaptation of the implementation of GCP is possible. This firstly takes into account the characteristics of the research: which objectives/which risks/which challenges. The options in terms of adaptation must be pre-defined, documented and justified; if necessary, they will also be re-assessed in the course of analysis.

Safety pharmacology: an essential interface of pharmacology and toxicology in the non-clinical assessment of new pharmaceuticals

Safety pharmacology studies are defined as the studies that investigate the potential undesirable pharmacodynamic effects of a substance on physiological functions in relation to exposure. In consequence, these studies are an integral part of the non-clinical safety assessment of new pharmaceuticals, in association with toxicological studies. A retrospective shows the evolution of the discipline in these last years. Safety pharmacology studies are of special interest, and some drawbacks and pitfalls must be considered (i.e. invasive methods, difficulties related to GLP (good laboratory practices) requirements, choice of a strategy). In the future, some priority should be given to education, promotion of scientific activities, reinforcement of the links between pharmacologists and toxicologists and implementation of relevant guidelines.

Origins, practices and future of safety pharmacology

The origins of safety pharmacology are grounded upon observations that organ functions (like organ structures) can be toxicological targets in humans exposed to novel therapeutic agents, and that drug effects on organ functions (unlike organ structures) are not readily detected by standard toxicological testing. Safety pharmacology is " em leader those studies that investigate the potential undesirable pharmacodynamic effects of a substance on physiological functions in relationship to exposure in the therapeutic range and above em leader " [International Conference on Harmonization (ICH) S7A guidelines; Safety Pharmacology Studies for Human Pharmaceuticals]. This publication provides a comprehensive review of the history of safety pharmacology, international regulatory guidelines that govern the practices of this important field, and the scientific challenges that are being faced by its rapid emergence in pharmaceutical development. The criticality of identifying undesired adverse effects of new drugs in nonclinical models, which reflect the overall human condition, is reflected in the importance of generating an integrated and accurate assessment of possible human risk. The conundrum posed by the challenge of formulating a reliable risk assessment is the importance of improving and enhancing the safe progression of new drugs to the marketplace, while preventing unnecessary delays (or discontinuances), based on nonclinical findings that are not relevant or interpretable in terms of clinical response or human risk.

Impact of a short postgraduate course in rational pharmacotherapy for general practitioners

AIMS

The impact of a short postgraduate course on rational pharmacotherapy planning behaviour of general practitioners (GP) was investigated via a face-to-face interview with 25 GPs working at health centres in Istanbul.

METHODS

GPs were randomly allocated to control and intervention groups. Intervention group attended a 3-day-training program preceded and followed by a written exam to plan treatment for simulated cases with a selected indication. The participants' therapeutic competence was also tested at the post-test for an unexposed indication to show the transfer effect of the course. In addition, patients treated by these GP's were interviewed and the prescriptions were analysed regarding rational use of drugs (RUD) principles at the baseline, 2 weeks and 4 months after the course.

RESULTS

At the baseline there was not any significant difference between the control and intervention groups in terms of irrational prescribing habits. The questionnaires revealed that the GPs were not applying RUD rules in making their treatment plans and they were not educating their patients efficiently. Training produced a significant improvement in prescribing habits of the intervention group, which was preserved for 4 months after the course. However, very low scores of the pretest indicate the urgent necessity for solutions.

CONCLUSIONS

Training medical doctors on RUD not only at the under- but also at the postgraduate level deserves attention and should be considered by all sides of the problem including academia, health authorities and medical associations.

International Union of Pharmacology. XXV. Nomenclature and classification of adenosine receptors

Four adenosine receptors have been cloned and characterized from several mammalian species. The receptors are named adenosine A(1), A(2A), A(2B), and A(3). The A(2A) and A(2B) receptors preferably interact with members of the G(s) family of G proteins and the A(1) and A(3) receptors with G(i/o) proteins. However, other G protein interactions have also been described. Adenosine is the preferred endogenous agonist at all these receptors, but inosine can also activate the A(3) receptor. The levels of adenosine seen under basal conditions are sufficient to cause some activation of all the receptors, at least where they are abundantly expressed. Adenosine levels during, e.g., ischemia can activate all receptors even when expressed in low abundance. Accordingly, experiments with receptor antagonists and mice with targeted disruption of adenosine A(1), A(2A), and A(3) expression reveal roles for these receptors under physiological and particularly pathophysiological conditions. There are pharmacological tools that can be used to classify A(1), A(2A), and A(3) receptors but few drugs that interact selectively with A(2B) receptors. Testable models of the interaction of these drugs with their receptors have been generated by site-directed mutagenesis and homology-based modelling. Both agonists and antagonists are being developed as potential drugs.

The new pre-preclinical paradigm: compound optimization in early and late phase drug discovery

The attrition rates of new chemical entities (NCEs) in preclinical and clinical development are staggeringly high. NCEs are abandoned due to insufficient efficacy, safety issues, and economic reasons. Uncovering drug defects that produce these failures as early as possible in drug discovery would be highly effective in lowing the cost and time of developing therapeutically useful drugs. Unfortunately, there is no single factor that can account for these NCE failures in preclinical and clinical development since factors, such as solubility, pKa, absorption, metabolism, formulation, pharmacokinetics, toxicity and efficacy, to name a few, are all interrelated. In addition, there are many problems in scaling-up drug candidates from the laboratory bench scale to the pilot plant scale. To address the problem of attrition rates of NCEs in preclinical and clinical development and drug scale-up issues, pharmaceutical companies need to reorganize their preclinical departments from a traditional linear approach to a parallel approach. In this review, a strategy is put forth to integrate certain aspects of drug metabolism/pharmacokinetics, toxicology functions and process chemistry into drug discovery. Compound optimization in early and late phase drug discovery occurs by relating factors such as physicochemical properties, in vitro absorption, in vitro metabolism, in vivo pharmacokinetics and drug scale-up issues to efficacy optimization. This pre-preclinical paradigm will improve the success rate of drug candidates entering development.

Publishing pharmacology in the twenty-first century

The World Wide Web and other forms of digital communication have lead some to predict the demise of printed journals. In my experience, scientific articles can be more efficiently reviewed and edited by digital document sharing. High quality print journals will remain the preferred scholarly venue for authors' best works, but only if the ethical behavior of scientists can be maintained and appropriately rewarded.

Quality use of medicines: where does pharmacology 'end'? Invited ASCEPT Lecture. Australasian Society of Clinic and Experimental Pharmacologists and Toxicologists

1. Pharmacology can be defined very narrowly (e.g. as solely a laboratory based specialty) or more broadly to include issues surrounding rational drug use in the community. 2. While the hypothetio-deductive approach is more clearly in evidence in laboratory and clinical pharmacological experimentation, it is no less important in the comparatively less-well charted area of drug use in the community. 3. Just as laboratory pharmacology has built new partnerships with molecular biology and genetics, the exploration of community drug use brings pharmacologists into partnership with other disciplines (epidemiology, economics, behavioural science) and other sectors (consumers, government, health professionals and industry). 4. Implementing Australia's Quality Use of Medicines Policy (1992) has led to vigorous exploration of issues and problems in medicinal drug use in the community and much scientific study of causes and potential interventions to improve the situation. 5. The Australian National Prescribing Service (1998) is attempting to bring an evidence-based approach to the many facets of prescribing and drug use, by prescribers and consumers alike. 6. Innovation commonly occurs at the interface between the boundaries of traditional disciplines.

International union of pharmacology. XXII. Nomenclature for chemokine receptors

Chemokine receptors comprise a large family of seven transmembrane domain G protein-coupled receptors differentially expressed in diverse cell types. Biological activities have been most clearly defined in leukocytes, where chemokines coordinate development, differentiation, anatomic distribution, trafficking, and effector functions and thereby regulate innate and adaptive immune responses. Pharmacological analysis of chemokine receptors is at an early stage of development. Disease indications have been established in human immunodeficiency virus/acquired immune deficiency syndrome and in Plasmodium vivax malaria, due to exploitation of CCR5 and Duffy, respectively, by the pathogen for cell entry. Additional indications are emerging among inflammatory and immunologically mediated diseases, but selection of targets in this area still remains somewhat speculative. Small molecule antagonists with nanomolar affinity have been reported for 7 of the 18 known chemokine receptors but have not yet been studied in clinical trials. Virally encoded chemokine receptors, as well as chemokine agonists and antagonists, and chemokine scavengers have been identified in medically important poxviruses and herpesviruses, again underscoring the importance of the chemokine system in microbial pathogenesis and possibly identifying specific strategies for modulating chemokine action therapeutically. The purpose of this review is to update current concepts of the biology and pharmacology of the chemokine system, to summarize key information about each chemokine receptor, and to describe a widely accepted receptor nomenclature system, ratified by the International Union of Pharmacology, that is facilitating clear communication in this area.

Programme to improve the use of drugs in older people and involve general practitioners in community education

As part of a multi-pronged approach to improving the quality of drug use in the elderly, a pharmacist was contracted by the Division of General Practice (Northern Tasmania) to develop educational material and implement two academic detailing sessions for general practitioners on the issues of adverse drug reactions and drug interactions in older people. The project aimed to involve general practitioners in community education after optimizing relevant therapeutic knowledge and standardizing prescribing practices. Sixteen general practitioners were involved in the project and 13 of these agreed to participate in academic detailing. The pharmacist developed prescribing guidelines for general practitioners and discussed these and illustrative case studies at the academic detailing sessions. General practitioner-conducted education sessions were completed by nine general practitioners to groups of carers, general practitioners, nurses and older people. Despite the relatively low numbers of general practitioners involved, the results of the project were encouraging. Academic detailing by the pharmacist was well received by the general practitioners, who indicated they would be willing to participate in further sessions. Pre- and post-project multiple-choice tests on therapeutic issues in the elderly indicated a strong trend for an increase in knowledge. Analysis of general practitioners' patient records found a statistically significant decline in the median number of medications prescribed per patient during the project. There was also a statistically significant decline in prescribing of 'indicator' medications, particularly psychoactive drugs and nonsteroidal anti-inflammatory drugs in patients resident in nursing homes. The project demonstrated that academic detailing by a pharmacist can be effective as part of a combined approach to improve the quality of drug use in older people.

Development and submission of a nonclinical (pharmacology/toxicology) CANDA

The experience with the submission of a nonclinical (pharmacology and toxicology) computer-assisted New Drug Application (CANDA) is reviewed. This system consisted of a stand-alone personal computer running several commercial programs in Microsoft Windows to access both text and data. WordPerfect was used as the word processor that contained all the documents and data tables (in read-only format) that were submitted in hard copy, and Andyne GQL was used as a tool to query the data in an Oracle relational database. Microsoft Excel was provided as a spreadsheet for graphics and analysis of data. Documents appeared virtually identical to those in the hard copy NDA submission. Searching the text was facilitated by the use of buttons on the screen, which allowed the NDA to be searched for a particular term. Data could be located either in WordPerfect documents, or in an Oracle database (using Andyne GQL) by querying the data. The data queries could be performed ad hoc, in which the reviewer selected all the parameters for a search, or with predefined query buttons, which retrieved data for principal treatment-related changes. This type of system also could serve as a useful model for both in-house nonclinical review and the submission of INDs and IND amendments.

In vitro/in vivo correlations: scientific implications and standardisation

In vitro/in vivo correlations and the parameters that should be correlated have now been well defined in the USP and FDA working group proposals. Among the three levels of correlation defined, Level A is the most interesting one. In this paper, the Level A correlation is studied from a mathematical and a biopharmaceutical point of view. The conditions that must be met before attempting to establish correlations and the place of in vitro/in vivo correlation in modified release drug dosage form development are discussed. To establish in vitro/in vivo correlations requires a strict development methodology in order to obtain them in the most favourable conditions. In vitro/in vivo correlations should be sought as early as possible during the dosage form development (a priori correlations). If the formulation has been undertaken first and correlations sought on the finished product from subsequent in vitro tests, the predictive power of these correlations (a posteriori correlations) is thus limited and they require additional validation.

General estimation of relative potency using prior information

A general point and interval estimator of the log relative potency is exhibited in closed form, which incorporates prior information on the log relative potency for symmetrical as well as asymmetrical parallel line bioassay. The point estimator turns out to be a weighted average of the usual estimator and the prior mean where the weights are determined by the prior variance.