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A new group of hypoglycemic drugs has been used to treat diabetes type 2. This group is active sodium glucose co-transporter (SGLT2) or SGLT2 inhibitors. It has been shown that besides the treatment of diabetes, this drug class is responsible for the mildness of the cardiovascular events shown in patients with diabetes type 2. However, there is an intriguing question regarding the range of SGLT2 inhibitors and if there is a difference between them or if there is a class effect among their results. EMPA-REG OUTCOME trial and the CVD-study are used to answer this question. Additional information from the DECLARE-TIMI 58 and Dapa-HF trials is studied.

Purpose: To determine if fluorescein angiographic (FA) findings after intravitreal ranibizumab (IVR) for retinopathy of prematurity (ROP) conform to a class effect previously described with bevacizumab. Methods: Single-center retrospective case series of all infants treated with 0.2 mg (0.02 mL) IVR for Type 1 ROP from July 2016 to November 2018. FA were obtained at 40, 52, 62, and 72 weeks of postmenstrual age (PMA) using wide-angle photography. FA images were analyzed and the peripheral avascular areas measured with ImageJ using a reference disc diameter (DD). Based on the extent of the avascular area and tortuosity of the retinal vessels all eyes were classified into four categories: complete vascular maturity (vascularization within 2 DD of the ora serrata), VAA (avascular area >2 DD of the ora serrata), VAT (avascular area >2 DD of the ora serrata and posterior tortuosity), and reactivation (recurrence of stage disease). Results: About 13 infants were enrolled and 24 eyes were available in this study. None of the eyes reached complete vascular maturity at an average PMA of 60 weeks, 7 (29%) eyes presented with VAA, 8 (33%) with VAT, and 9 (37.5%) reactivated. The reactivated eyes presented with the largest area of peripheral ischemia, followed by the VAT and then the VAA groups ( p = 0.02). Conclusion: IVR conforms to the previously described regression patterns following intravitreal bevacizumab for ROP indicative of a class effect. Follow-up using FA might help to optimize the management of these infants after injection of the drug.

Background Network meta-analysis synthesises data from a number of clinical trials in order to assess the comparative efficacy of multiple healthcare interventions in similar patient populations. In situations where clinical trial data are heterogeneously reported i.e. data are missing for one or more outcomes of interest, synthesising such data can lead to disconnected networks of evidence, increased uncertainty, and potentially biased estimates which can have severe implications for decision-making. To overcome this issue, strength can be borrowed between outcomes of interest in multivariate network meta-analyses. Furthermore, in situations where there are relatively few trials informing each treatment comparison, there is a potential issue with the sparsity of data in the treatment networks, which can lead to substantial parameter uncertainty. A multivariate network meta-analysis approach can be further extended to borrow strength between interventions of the same class using hierarchical models. Methods We extend the trivariate network meta-analysis model to incorporate the exchangeability between treatment effects belonging to the same class of intervention to increase precision in treatment effect estimates. We further incorporate a missing data framework to estimate uncertainty in trials that did not report measures of variability in order to maximise the use of all available information for healthcare decision-making. The methods are applied to a motivating dataset in overactive bladder syndrome. The outcomes of interest were mean change from baseline in incontinence, voiding and urgency episodes. All models were fitted using Bayesian Markov Chain Monte Carlo (MCMC) methods in WinBUGS. Results All models (univariate, multivariate, and multivariate models incorporating class effects) produced similar point estimates for all treatment effects. Incorporating class effects in multivariate models often increased precision in treatment effect estimates. Conclusions Multivariate network meta-analysis incorporating class effects allowed for the comparison of all interventions across all outcome measures to ameliorate the potential impact of outcome reporting bias, and further borrowed strength between interventions belonging to the same class of treatment to increase the precision in treatment effect estimates for healthcare policy and decision-making.

Bradykinin-mediated angioedema is a rare but potentially fatal adverse event. Angioedema induced by angiotensin-converting enzyme (ACE) inhibitors is generally attributed to an inhibition of bradykinin degradation following ACE inhibition. Clinical studies on ACE inhibitors mainly focus on their efficacy. Few examine their potential to generate undesirable adverse effects, particularly with regard to angioedema.We report here a case of angioedema occurring after ramipril initiation in a patient chronically treated with quinapril. Angioedema subsided spontaneously after ramipril discontinuation and quinapril reintroduction.Our clinical case suggests that despite similar pharmacodynamic properties, quinapril and ramipril do not have the same potential to generate angioedema. To explain this difference, we suggest a potentiation of the effect of bradykinin at the B2 receptor level by ramipril, which does not occur with quinapril. Consequently, angioedema may not always be a class effect of ACE inhibitors.

Purpose: To provide a comprehensive review to determine whether there is a class effect among angiotensin receptor blockers (ARBs) in relation to serum uric acid. Summary: A literature search was conducted and 8 articles were identified for inclusion in this review. In the studies reviewed, candesartan and valsartan were shown to have either a neutral or negative effect on serum uric acid. Azilsartan was shown to have a negative impact on serum uric acid while eprosartan appeared to have no impact on serum uric acid levels. Irbesartan demonstrated either a neutral or positive effect on serum uric acid while losartan exhibited a positive effect. Conclusion: The available data indicate that the reduction of serum uric acid is not a class effect of ARBs. Of the available agents, only losartan has clear evidence of its ability to lower serum uric acid. For patients with high blood pressure and elevated serum uric acid, losartan should be considered as a first-line agent with irbesartan as an alternative when appropriate.

Aims In 2008, the US Food and Drug Administration (FDA) issued a guidance requiring that cardiovascular outcome trials (CVOTs) be conducted for newer hypoglycaemic drugs for type 2 diabetes (T2D). We aimed to examine the decisions by 3 regulatory authorities in response to identical CVOT data. Methods We surveyed ClinicalTrials.gov to identify CVOTs and examined the revision histories of drug labels in databases from the FDA, the European Medicines Agency, and the Pharmaceuticals and Medical Devices Agency in Japan. Results We selected 14 drugs and corresponding CVOTs, 12 of which were conducted as postmarketing trials. In the USA and the EU, the pre-CVOT indication on all 14 labels was "improvement in glycaemic control". Six drugs showed significant cardiovascular risk reduction, which led to an additional indication regarding reduction of cardiovascular adverse events in the USA, and a change to the EU indication to specify treatment of adults with T2D. The initial indication in Japan, T2D, remained unchanged. Regarding safety, significant increases in heart failure were observed only in the saxagliptin trial. A warning was added to the saxagliptin labels in the EU and Japan, whereas the FDA required a class effect warning to be added to the labels of all 4 dipeptidyl peptidase-4 inhibitors. Conclusions Regulatory authorities using identical trial data made substantially different decisions regarding both safety and efficacy of hypoglycaemic drugs. The differences in initial indication wording between Japan and the other authorities suggest that trial data and T2D are interpreted differently in these regions.

Hospitalization for major diabetes complications, including myocardial infarction, stroke, lower-extremity amputation, and end-stage kidney disease, is on the rise and represents a great health burden for patients with type 2 diabetes (T2D), in particular for older people. Newer glucose-lowering medications have generated some optimism on the possibility to influence the natural history of cardiorenal complications of T2D. This review summarizes work in the area of sodium–glucose cotransporter 2 inhibitors (SGLT-2i) treatment and prevention of cardiorenal complications in patients with T2D (major adverse cardiovascular events, hospitalization for heart failure, kidney outcomes), with a particular emphasis on the effect of age, the role of primary versus secondary prevention and the possible extension of their cardiorenal benefits to the entire class of SGLT-2i.

Pharmacological target-mediated drug disposition (TMDD) represents a special source of nonlinear pharmacokinetics, and its occurrence in large-molecule compounds has been well recognized because numerous protein drugs have been reported to have TMDD due to specific binding to their pharmacological targets. Although TMDD can also happen in small-molecule compounds, it has been largely overlooked. In this mini-review we summarize the occurrence of TMDD that we discovered recently in a series of small-molecule soluble epoxide hydrolase (sEH) inhibitors. Our journey started with an accidental discovery of target-mediated kinetics of 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl]urea (TPPU), a potent sEH inhibitor, in a pilot clinical study. To confirm what we observed in human, we conducted a series of mechanism experiments in animals, including pharmacokinetic experiments using sEH-knockout mice as well as in vivo displacement experiments with co-administration of another potent sEH inhibitor. Our mechanism studies confirmed that the TMDD of TPPU is due to its pharmacological target sEH. We further expanded our evaluation to various other sEH inhibitors and found that TMDD is a class effect of this group of small-molecule sEH inhibitors. In addition to summarizing the occurrence of TMDD in sEH inhibitors, in this mini-review we also highlighted the importance of recognizing TMDD of small-molecule compounds and its impact in clinical development as well as utilizing pharmacometric modeling in facilitating quantitative understanding of TMDD.

Objective The aim of this study was to assess the causality of anti-TNFα agents-associated pleuropericarditis in VigiBase with a focus on its diverse types. Methods All variables contained in the pleuropericarditis reports were reviewed. Well-documented reports, vigiGrade completeness score ≥ 0.80 or with an informative narrative, were analyzed and with a focus on the clinical features of the cases. Bradford-Hill criteria were used in the case series assessment of causality. Results From 1968 up to 18 December 2019, there were 94 unique cases from 18 countries reporting pleuropericarditis with anti-TNFα agents as a suspected or interacting medicine. Among the 94 reports, 42 were identified as well-documented and further assessed for clinical features. Of the 42 cases, 39 were serious, including three fatal and seven life-threatening. In 35 cases, an anti-TNFα agent was the only suspected drug. Positive de- and re-challenge were reported in 95% and 17% of the 42 cases, respectively. The times to onset (TTO) varied greatly among individual cases, ranging from one month to 75 months (mean = 24 months). The most commonly involved anti-TNFα agents were adalimumab, infliximab and etanercept; and the mostly reported pleuropericarditis types were classified as autoimmune-related with (n = 17) or without (n = 15) co-reported drug-induced lupus (DIL), or infection-related (n = 8). While adalimumab was the most reported in the infection-related cases (7/8), infliximab was the most frequent in the autoimmune-related cases, in particular co-reported with DIL (9/17). There were four cases where the reaction occurred one to two months after the anti-TNFα agents (infliximab and adalimumab) were stopped. Based on the review of the case series using Bradford-Hill criteria the anti-TNFα agents associated pleuropericarditis are considered as a class effect. Conclusions To clinically recognize and manage these potentially life-threatening serious cardiopulmonary complications, health care professionals should be aware of this possible risk. Meanwhile, attention should be paid to the clinical features of pleuropericarditis cases, since they may cause diagnostic and therapeutic difficulties. Considering the long elimination time, clinicians need to be reminded to remain vigilant for the adverse reactions even after discontinuing anti-TNFα therapy.

Objectives There are increasing concerns regarding proton pump inhibitor (PPI) use and the risk of fractures in adults. Few studies have evaluated this risk among pediatric patients. This study examined fractures and fracture location among pediatric patients exposed to PPI compared with those without documented exposure. Study design Encounters for patients 6 months to 15.5 years were identified between July 1, 2011 to December 31, 2015 in the Pediatric Hospital Information System database. Exclusion criteria was applied for chronic illnesses, conditions or medications predisposing to fracture. Encounters were classified as PPI encounters if a charge for PPI was documented. PPI encounters were propensity matched to non-PPI encounters. Following initial encounter, patients were evaluated over a 2-year period for hospitalizations resulting from fracture. Results There was a statistically significant higher rate of fractures among the PPI-exposed group (1.4% vs 1.2%, P = 0.019). Adjusting for remaining differences in sex, race, encounter type, payer, and resource intensity after matching, the difference remained statistically significant (P = 0.017) with an adjusted odds ratio (95% CI) of 1.2 (1.0--1.4). Upper extremity was the most common location for fracture; however, the PPI cohort was more likely to suffer from lower extremity, rib, and spinal fractures (P = 0.01). Conclusions This study suggests an increased risk of fracture among pediatric patients taking PPI. Among patients hospitalized with a fracture, those with PPI exposure had a higher rate of lower extremity, rib, and spine fractures compared with controls. This appeared to be a class effect not related to individual PPI agent.

Maternal immunization with reduced antigen content tetanus-diphtheria-acellular pertussis (Tdap)-containing vaccines has been recommended to prevent infant pertussis. However, maternal antibodies may interfere with infant responses to routine immunization with diphtheria-tetanus-acellular pertussis (DTaP)-containing vaccines, raising concerns of suboptimal protection after infant vaccination. We performed a narrative literature review to assess whether blunting occurs regardless of the manufacturer of maternal and infant vaccines. Because internationally agreed correlates of protection are lacking, the clinical significance of blunting is not yet fully understood. We have reviewed the evidence available to date.Thirteen studies that evaluated blunting after maternal immunization and infant primary/booster series were identified. Blunting was observed with various combinations of Tdap- and DTaP-containing vaccines for maternal and pediatric immunization. Studies assessing the effectiveness of maternal Tdap immunization beyond the primary infant immunization series in England and in the United States suggested no evidence of a clinically relevant blunting effect so far.This review indicates that the phenomenon of blunting does not depend on the manufacturer/brand of the pertussis-containing vaccines used for immunizing mothers or children. Currently, there is no epidemiological evidence that children whose mothers received Tdap are at increased risk of pertussis after pediatric vaccinations, although longer follow-up is required.

Background:The atypical antipsychotics (AAPs) are associated with a recognized class effect of glucose and lipid dysregulation. The use of these medications is rapidly increasing in elderly patients with, and without, dementia. However, the metabolic risks specific to elderly remain poorly studied.Methods:Design: A case-control study.Setting: Psychogeriatric service in Auckland, New Zealand.Participants: Elderly patients either receiving AAP treatment (cases) or not (controls) between 1 Jan 2008 and 1 Jan 2014.Main outcome measures: metabolic data of glucose, HbA1c, lipids, and cardiovascular events and death. The data were analyzed usingt-tests and linear regression models for each metabolic outcome.Results:There were 330 eligible cases and 301 controls from a total study population of 5,307. There was a statistically significant change in the HbA1c over time, within the cases group of −1.14 mmol/mol (p = 0.018, 95% CI −0.19 to −2.09). Also statistically significant was the reduction in total cholesterol of −0.13 mmol/L (p = 0.036, 95% CI −0.008 to −0.245). The only significant difference found between cases and controls was in the change in cholesterol ratio of 0.16 mmol/L between groups (95%CI 0.01–0.31, p = 0.036).Conclusions:AAP use was not associated with any clinically significant change in metabolic outcomes in this study population.

The Food and Drug Administration (FDA) is advising health care practitioners that lamotrigine (Lamictal), used in managing seizures and bipolar disorder, may increase the risk of serious and potentially lethal arrythmias.The risk is greater if the patient has underlying cardiac disease or is taking medications that affect heart conduction.The FDA is requiring in vitro studies of other sodium channel blockers to determine if this risk is a class effect or unique to lamotrigine.

A direct comparison of the effects of febuxostat and allopurinol on flow-mediated dilatation (FMD) will help to clarify which agent provides a better reduction of cardiovascular risk in hypertensive patients. Hypertensive patients with hyperuricemia were randomized into a febuxostat (10-40 mg, n = 33) or allopurinol (100-200 mg, n = 31) group and followed up for 6 months. Both the febuxostat (7.9 ± 1.3 mg/dL vs 5.6 ± 1.0 mg/dL, P < .001) and allopurinol (8.2 ± 1.3 mg/dL vs 6.1 ± 1.0 mg/dL, P < .001) groups exhibited significant reductions in uric acid after treatment. There was no significant difference in the change in FMD between the two treatment groups (0.6 ± 2.6% vs 0.2 ± 2.3%, P = .504). However, stratified analysis showed that febuxostat achieved a significantly greater change in FMD compared to allopurinol in the elderly group (1.3 ± 2.9% vs -0.7%±1.8%, P = .047). There was no difference in the improvement of FMD between febuxostat and allopurinol, but febuxostat may provide an improvement of FMD in elderly people.

We read with interest the review article by Chretien et al, “Comparative study of hypoglycemia induced by opioids. Is it a class effect?” published online in this journal [1]. The authors performed...

Very late stent thrombosis (VLST) has been recognized as a class effect of 1st generation drug eluting stents (DES) implantation. Although rare, VLST has been reported between 1 and 4 years after DES implantation. Very very late stent thrombosis (VVLST) occurring more than 5 years after DES implantation is extremely rare. We report the first case of a VVLST from India occurring 3465 days (9.5 years) after DES implantation with a brief discussion on its pathogenesis and prevention.

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) and dipeptidyl peptidase-4 (DPP-4) inhibitors are so called “incretin-based therapies” (IBTs) that represent innovative therapeutic approaches and are commonly used in clinical practice for the treatment of type 2 diabetes mellitus (T2DM). The cardiovascular outcome trials (CVOTs) have provided useful information that has helped to shape changes in clinical practice guidelines for the management of T2DM. At the same time, the mechanisms that may explain the nonglycemic and cardiovascular (CV) benefits of these medications are still being explored. A summary of the main findings from CVOTs performed to-date with particular emphasis on various outcomes and inconsistencies observed in the trials is provided. Overall, available data is favourable to the early deployment of GLP-1RAs in clinical practice, fully in line with recommendations from international scientific guidelines, and based on their effects on glucose metabolism parameters, body weight reduction and CV outcomes. Evidence further suggest that the CV benefits of GLP-1RAs may not be a class effect, with GLP-1 analogues having a greater benefit rather than exendin-based agents.

Magnetic resonance imaging has become an indispensable tool for studying associations of structural and functional properties of the brain with behavior in humans. However, generally recognized standards for assessing and reporting the reliability of these techniques are still lacking. Here, we introduce a new approach for assessing and reporting reliability, termed intra-class effect decomposition (ICED). ICED uses structural equation modeling of data from a repeated-measures design to decompose reliability into orthogonal sources of measurement error that are associated with different characteristics of the measurements, for example, session, day, or scanning site. This allows researchers to describe the magnitude of different error components, make inferences about error sources, and inform them in planning future studies. We apply ICED to published measurements of myelin content and resting state functional connectivity. These examples illustrate how longitudinal data can be leveraged separately or conjointly with cross-sectional data to obtain more precise estimates of reliability.

A new era in antiembolic therapy has been initiated by the growing numbers of device-based therapies. Early concerns surrounding eliminating this enigmatic structure have not proven true. Other benefits are being further evaluated. Many other questions remain, such as whether there is a device-specific outcome effect or whether it is a class effect. Other questions include other devices, what head-to-head studies will show, and the impact of residual leak. Left atrial appendage using the Watchman ablation strategy can reduce cardioembolic stroke, with comparable or fewer adverse effects by device technology than obtained by long-term anticoagulation with its attendant bleeding risks.

Diabetes & Metabolism - In Press.Proof corrected by the author Available online since mardi 20 mars 2018

At the seven-year anniversary of the first catheter-based renal denervation procedure for resistant hypertension, it is timely to reflect on the past, present, and future of the development and clinical application of this treatment. Unresolved procedural and technical questions are central: How much renal denervation is optimal? How can this level of denervation be achieved? What test for denervation can be applied in renal denervation trials? Will renal denervation show a "class effect," with the different energy forms now used for renal nerve ablation producing equivalent blood pressure lowering? When I have assessed renal denervation efficacy, using measurements of the spillover of norepinephrine from the renal sympathetic nerves to plasma, the only test validated to this point, denervation was found to be incomplete and non-uniform between patients. It is probable that the degree of denervation has commonly been suboptimal in renal denervation trials; this criticism applying with special force to the Symplicity HTN-3 trial, where the proceduralists, although expert interventional cardiologists, had no prior experience with the renal denervation technique. Recently presented results from the Symplicity HTN-3 trial confirm that renal denervation was not achieved effectively or consistently. Given this, and other difficulties in the execution of the trial relating to drug adherence, an idea mooted is that the US pivotal trial of the future may be in younger, untreated patients.

Background In proteomics, batch effects are technical sources of variation that confounds proper analysis, preventing effective deployment in clinical and translational research. Results Using simulated and real data, we demonstrate existing batch effect-correction methods do not always eradicate all batch effects. Worse still, they may alter data integrity, and introduce false positives. Moreover, although Principal component analysis (PCA) is commonly used for detecting batch effects. The principal components (PCs) themselves may be used as differential features, from which relevant differential proteins may be effectively traced. Batch effect are removable by identifying PCs highly correlated with batch but not class effect. However, neither PC-based nor existing batch effect-correction methods address well subtle batch effects, which are difficult to eradicate, and involve data transformation and/or projection which is error-prone. To address this, we introduce the concept of batch-effect resistant methods and demonstrate how such methods incorporating protein complexes are particularly resistant to batch effect without compromising data integrity. Conclusions Protein complex-based analyses are powerful, offering unparalleled differential protein-selection reproducibility and high prediction accuracy. We demonstrate for the first time their innate resistance against batch effects, even subtle ones. As complex-based analyses require no prior data transformation (e.g. batch-effect correction), data integrity is protected. Individual checks on top-ranked protein complexes confirm strong association with phenotype classes and not batch. Therefore, the constituent proteins of these complexes are more likely to be clinically relevant. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3490-3) contains supplementary material, which is available to authorized users.

Proton pump inhibitors (PPIs) are not widely recognized as a cause of drug-induced thrombocytopenia. Literature is mainly confined to case reports and has been insufficient to explore the possibility that this adverse event may be attributed to a class effect of PPI therapy. We present a case where platelet counts dropped from 177 (×10(3) per mm(3)) to 47 (×10(3) per mm(3)) within 6 days after the patient was switched from omeprazole to pantoprazole. There have been case reports of thrombocytopenia caused by PPIs; however, this is noted to be extremely rare. In our case, the patient developed thrombocytopenia on two separate occasions of exposure to pantoprazole, which resolved after stopping the medicine, thus providing definite proof of pantoprazole causing thrombocytopenia. Moreover, the patient did not have thrombocytopenia with omeprazole, thus suggesting that thrombocytopenia with PPIs might be an individual drug effect rather than a class effect. This occurrence has been reported in three other case reports as well. From the nine case reports that we have reviewed, direct causal relationship was found in a few reports only. It has been hypothesized that this adverse effect may be immune mediated, but further investigations are still needed to identify the exact pathogenesis.

Diagnostic tests have become increasingly important for optimizing drug use. Ideally, a companion diagnostic test is developed concurrently with a corresponding therapeutic product (co-development). However, the diagnostic test may also be developed to optimize treatment with previously approved therapeutic agents (follow-up-development). In co-development, the effectiveness of an agent in marker-defined patients is confirmed by an enrichment trial design. In follow-up-development, a biomarker is validated by prospective and/or retrospective analyses of unselected design trials. A prospectively designed trial is the gold-standard approach to biomarker validation, but retrospective validation can be used to efficiently determine effective treatments for marker-defined patients. Accumulation and systematization of examples of drug-diagnostic development will aid in the effective development of companion diagnostics.

There is considerable interest in whether non-nutritive sweeteners are sensed in the gastrointestinal tract to modulate appetitive or absorptive responses to ingested carbohydrate. We determined the effect of a panel of non-nutritive sweeteners, aspartame, saccharin and acesulfame-K, delivered in doses that would be consumed in normal usage. Each was given in combination with glucose, assessing their effect on glycemic responses and appetite in ten healthy human subjects. There was no additional effect of aspartame or saccharin on the blood glucose response to oral glucose at any time point, although acesulfame-K exerted a small effect. However, none had an effect on perceptions of hunger or fullness. We conclude that there is no consistent evidence that non-nutrient sweeteners, when acutely consumed with glucose in dietetically relevant doses, have a class effect in modulating blood glucose in healthy human subjects. However, acesulfame-K may require further exploration.

In an increasing number of cases, a deeper understanding of the biochemical basis for idiosyncratic adverse drug reactions (IADRs) has aided to replace a vague perception of a chemical class effect with a sharper picture of individual molecular peculiarity. Considering that IADRs are too complex to duplicate in a test tube, and their idiosyncratic nature precludes prospective clinical studies, it is currently impossible to predict which new drugs will be associated with a significant incidence of toxicity. Because it is now widely appreciated that reactive metabolites, as opposed to the parent molecules from which they are derived, are responsible for the pathogenesis of some IADRs, the propensity of drug candidates to form reactive metabolites is generally considered a liability. Procedures have been implemented to monitor reactive-metabolite formation in discovery with the ultimate goal of eliminating or minimizing the liability via rational structural modification of the problematic chemical series. While such mechanistic studies have provided retrospective insight into the metabolic pathways which lead to reactive metabolite formation with toxic compounds, their ability to accurately predict the IADR potential of new drug candidates has been challenged. There are several instances of drugs that form reactive metabolites, but only a fraction thereof cause toxicity. This review article will outline current approaches to evaluate bioactivation potential of new compounds with particular emphasis on the advantages and limitation of these assays. Plausible reason(s) for the excellent safety record of certain drugs susceptible to bioactivation will also be explored and should provide valuable guidance in the use of reactive-metabolite assessments when nominating drug candidates for development.

The Heart Outcomes Prevention (HOPE) trial was the first to demonstrate the benefits of the angiotensin-converting enzyme (ACE) inhibitor ramipril for high-risk cardiovascular patients. Whether the cardioprotective effects seen in HOPE and other trials are specific to distinct ACE inhibitors remains controversial. Evidence of a lack of class effect for ACE inhibitors has policy and financial implications related to reference pricing by insurers and inclusion on pharmacy formularies. Because head-to-head trials comparing the different ACE inhibitors are unforeseen, clinicians and administrators must rely on secondary-level data and observational studies. Only a handful of studies have sought to address the dispute over a class effect among ACE inhibitors, which is reviewed in this article.

Venous thromboembolic events (VTEs) are frequent in cancer patients because of the effects of malignant disease, its treatment, and comorbidities. The higher risk for VTEs associated with the use of erythropoiesis-stimulating agents (ESAs) appears to be a class effect but may be particularly pronounced when these agents are used in patients who are not anemic at baseline and/or to achieve hemoglobin targets higher than those recommended in current labeling. Particular attention should be taken to assess the balance of risks and benefits in patients with a history of thromboembolism. If the goal of treatment of patients with chemotherapy-associated anemia is aimed to raise the hemoglobin level to 12 g/dl, and is confined to that, ESA-induced VTEs should rarely be a problem.

A few years ago the Food and Drug Administration, based on a meta-analysis, issued a warning stating that antiepileptic drugs (AEDs) are associated with an increased risk of suicidal ideation, suicide attempts, and completed suicide. This warning generated significant concern about the use of AEDs, especially in patients with epilepsy and affective disorders. Following the FDA report, several studies addressed this issue but only served to generate further concern and confusion. There seems to be no convincing data concerning a "class effect" of AEDs in inducing any type of suicide-related behaviors. Some data suggest a possible association of lamotrigine, levetiracetam, and topiramate with suicidality, but further research is needed. In any case, clinicians need to carefully assess suicidality in all patients treated with AEDs and inform them and their families on the possible increased risk of suicidality, though preferably in a way that keeps open the continuing use of AEDs.

Angiotensin-converting enzyme inhibitor therapy provides positive outcome benefits in a number of cardiac scenarios including congestive heart failure, postmyocardial infarction, as well as in the hypertensive patient at cardiac risk. This benefit exists both in normotensive and hypertensive individuals and is present in those with various grades of cardiovascular risk. This beneficial cardiovascular effect has now been observed with several angiotensin-converting enzyme inhibitors, suggesting a class effect. The Prevention of Events with Angiotensin-Converting Enzyme Inhibition trial studied the effect of adding the angiotensin-converting enzyme inhibitor trandolapril to a contemporary therapeutic regimen of patients with stable coronary artery disease and preserved left ventricular function. In this study, the addition of trandolapril did not confer any additional benefit in terms of reducing the incidence of cardiovascular death, myocardial infarction, or coronary revascularization. The neutral findings in this trial add a new wrinkle to the concept of class effect for cardiovascular protection with angiotensin-converting enzyme inhibitors in patients with coronary artery disease.

nephritis, with a further episode of acute interstitial nephritis when rechallenged with a different proton pump inhibitor (pantoprazole). Previous case studies have shown that reintroduction of the same proton pump inhibitor caused recurrent worsening of renal function. This is the first report of acute interstitial nephritis occurring secondary to two different proton pump inhibitors in the same individual. This strengthens the hypothesis that proton pump inhibitor-induced acute interstitial nephritis is a class effect and should raise caution when clinicians consider initiating another proton pump inhibitor in a patient who has previously been diagnosed with proton pump inhibitor-induced acute interstitial nephritis. Discussion Proton pump inhibitors are one of the most commonly prescribed drug classes and, in 2003, the Food and Drug Administration approved the sale of proton pump inhibitors 'over the counter'. The increased availability of these medications has lead to improved awareness and documentation of the side- effect profile. While proton pump inhibitor- induced acute interstitial nephritis is a rare

Our task as clinicians would be simple if all we had to do was to follow the logical sequence of identifying a biological target, finding a drug or treatment specifically affecting that target, testing the efficacy of the drug or treatment in appropriately designed clinical trials, and then prescribing only those drugs or treatments with proven efficacy and an acceptable safety profile. Drugs that affect a given biological target could be considered as a “class,” with those that show “efficacy” in clinical trials considered as therapeutic alternatives within that class. Unfortunately, the real world is not that simple. Defining precisely what we mean by class effect and efficacy becomes increasingly problematic, for example, as we have recently witnessed with calcium channel blockers, β-blockers, angiotensin-converting enzyme inhibitors, HMG CoA reductase inhibitors, glycoprotein IIb/IIIa antagonists, low-molecular-weight heparins, and direct thrombin antagonists.1 If we identify a drug that demonstrates efficacy, are the benefits of that drug generalizable to all drugs with similar biological targets?2 If benefits are present in one clinical circumstance, are those benefits generalizable to all circumstances in which that class of drugs can be applied?3 In the modern cost-conscious arena, can we substitute less expensive, mechanistically similar agents that may not have the same weight of clinical evidence support or even the same degree of clinical benefit? When is it acceptable to generalize to a class effect, or should we adhere strictly to evidence-based therapy with individual compounds? These issues can be viewed from both scientific and clinical perspectives. ### Definition of Biological Target As our scientific knowledge grows, our traditional grouping of drugs has become, to a large extent, obsolete. For example, there are 9 different calcium channel blockers that are approved for clinical use in the United States, which can be divided into 5 general groups on the basis of …

The noted myotoxicity and subsequent withdrawal of cerivastatin from the worldwide market in August 2001 has demonstrated that the safety of statins is not a class effect. The total rhabdomyolysis rate for cerivastatin was 16 - 80 times more frequent than with other statins without providing additional efficacy. Cerivastatin has a pharmacokinetic profile (high potency, bioavailability, lipophilicity and renal excretion) that is different from other statins, which may explain the high myotoxicity rate. The cerivastatin experience has also provided insights into high-risk populations (i.e., the elderly, women, those with renal impairment, co-administration of interacting drugs) that are more prone to statin-induced myopathy. Ultimately, the lessons learned from this experience may significantly improve the safety of statin use in the future.

Clarithromycin is an antibiotic of the macrolide family, which is commonly used in the treatment of respiratory tract infections. We report a woman aged 77 years with bronchiectasis who was prescribed oral clarithromycin for lower respiratory tract infection. She developed akathisia after 2 doses. On withdrawing the antibiotic, her symptoms resolved rapidly after 7 days.

Proton pump inhibitors (PPIs) have been linked to clinically symptomatic hypomagnesemia.We searched Medline database in all languages using 'proton-pump inhibitors, magnesium, hypomagnesemia and hypomagnesemic hypoparathyroidism' as search terms and other articles were identified through searches of the files of the authors and reference lists from relevant articles. All patients presented with hypomagnesemic hypoparathyroidism, however, they rarely had life-threatening conditions such as malignant ventricular arrhythmias associated with prolonged QT interval, tetany and generalized seizures. Hypomagnesemia was seen with different PPIs, which could suggest a class effect, and was refractory to Mg replacement until PPIs were stopped. Hypomagnesemia may recur after re-challenge with the same or a different PPI and is not clearly dose-related. Mechanisms are poorly understood but PPI-induced hypochlorhydria does not seem involved. Carriers of TRPM6/7 mutations could be at risk.Although mechanism and incidence rate remain unclear, there seems little doubt that PPIs may cause hypomagnesemia. We should obtain blood Mg levels prior to initiation of PPIs when patients are expected to be on treatment for long period of time and in those with other potential causes of hypomagnesemia. Use of H2-blockers may be an appropriate alternative.

Angiotensin-converting enzyme (ACE) inhibitors differ in their affinity for tissue-bound ACE. It has been hypothesized that tissue ACE affinity might be responsible for some of the beneficial cardiovascular properties of ACE inhibitors. The present study examined this question and found no correlation between tissue ACE affinity and risk of first nonfatal myocardial infarction in patients who have hypertension.