Early assessment of proarrhythmic risk of drugs using the in vitro data and single-cell-based in silico models: proof of concept

Background and purpose: To determine the predictive performance of in silico models using drug-specific preclinical cardiac electrophysiology data to investigate drug-induced arrhythmia risk (e.g. Torsade de pointes (TdP)) in virtual human subjects.

Experimental approach: To assess drug proarrhythmic risk, we used a set of in vitro electrophysiological measurements describing ion channel inhibition triggered by the investigated drugs. The Cardiac Safety Simulator version 2.0 (CSS; Simcyp, Sheffield, UK) platform was used to simulate human left ventricular cardiac myocyte action potential models.

Results: This study shows the impact of drug concentration changes on particular ionic currents by using available experimental data. The simulation results display safety threshold according to drug concentration threshold and log (threshold concentration/ effective therapeutic plasma concentration (ETPC)).

Conclusion and implications: We reproduced the underlying biophysical characteristics of cardiac cells resulted in effects of drugs associated with cardiac arrhythmias (action potential duration (APD) and QT prolongation and TdP) which were observed in published 3D simulations, yet with much less computational burden.     

First experiences with a tool to measure the level of clinical information present in adverse drug reaction reports

Background: To make a proper causality assessment of an adverse drug reaction (ADR) report, a certain level of clinical information is necessary. A tool was developed to measure the level of clinical information present in ADR reports. The aim of this study was to test the validity and reliability of the clinical documentation tool (ClinDoc) in an international setting.

Methods: The tool was developed by a panel of pharmacovigilance experts. It includes four domains: ADR, chronology of the ADR, suspected drug and patient characteristics. The final score categorizes reports into: excellent, well, moderately or poorly documented.

In two rounds, eight pharmacovigilance assessors of different countries made a total of 224 assessments using the tool, with the expert panels judgement as a standard. Sensitivity and specificity were calculated.

Results: The tool with four outcome-categories demonstrated low sensitivity. A lack of distinctiveness was demonstrated between the categories moderate and well. Results for the second round were re-analysed using three categories. This demonstrated a better validity.

Conclusion: This is the first tool to give insight in the level of relevant clinical information present in ADR reports. It can be used internationally to compare reports coming from different reporting methods and different types of reporters in pharmacovigilance.     

Effects of phillyrin and forsythoside A on rat cytochrome P450 activities in vivo and in vitro

1. Phillyrin and forsythoside A are two important active ingredients in Forsythia suspensa. However, the effects of phillyrin and forsythoside A on the activities of cytochrome P450 (CYP450) remain unclear.

2. This study aimed to investigate the effects of phillyrin and forsythoside A on the activities of CYP1A2, CYP2C11, CYP2D1 and CYP3A1/2 by cocktail probe drugs in rats both in vivo and in vitro.

3. Many pharmacokinetic parameters of caffeine and metoprolol in phillyrin pretreatment group, caffeine and tolbutamide in forsythoside A pretreatment group were affected significantly. In rat liver microsomal incubation system, the concentrations of acetaminophen and dextrophan in the phillyrin pretreatment group are higher than blank control group by 207.69% and 125.00%, however, the concentrations of 4-hydroxytolbutamide and 6β-hydroxytestosterone were not significantly altered. The concentrations of acetaminophen and 4-hydroxytolbutamide in the forsythoside A pretreatment group are higher than blank control group by 223.07% and 154.16%, whereas the concentrations of dextrophan and 6β-hydroxytestosterone were not significantly altered.

4. These results indicated that Phillyrin had potential inductive effects on rat CYP1A2 and CYP2D1 activities, without affecting CYP2C11 and CYP3A1/2 activities. Moreover, forsythoside A had inductive effects on the activities of CYP1A2 and CYP2C11, without affecting CYP2D1 and CYP3A1/2 activities.     

Dosing strategies to optimize currently available anti-MRSA treatment options (Part 2: PO options)

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is a problematic pathogen in both outpatient and inpatient settings. Research to optimize the dosing of these agents is needed to slow the development of antimicrobial resistance and to decrease the likelihood of clinical failure.

Areas covered: This review summarizes the available data for orally administered antimicrobials routinely used as monotherapy for MRSA infections. We make recommendations and highlight the current gaps in the literature. A PubMed (1966 – Present) search was performed to identify relevant literature for this review.

Expert commentary: There is a vast divide in the amount of pharmacokinetic/pharmacodynamic data to guide dosing decisions for older MRSA agents compared with the oxazolidenones.

Five-year view: Additional retrospective data will become available for the older MRSA agents in severe MRSA infections.     

Clinical trial transparency update: an assessment of the disclosure of results of company-sponsored trials associated with new medicines approved in Europe in 2012

Background:

The objective of this study was to assess the timely disclosure of results of company-sponsored clinical trials related to all new medicines approved by the European Medicines Agency (EMA) during 2012. This is an extension of the previously reported study of trials related to all new medicines approved in Europe in 2009, 2010 and 2011, which found that over three-quarters of all these trials were disclosed within 12 months and almost 90% were disclosed by the end of the study.

Methods:

The methodology used was exactly as previously reported. Various publicly available information sources were searched for both clinical trial registration and disclosure of results. All completed company-sponsored trials related to each new medicine approved for marketing by the EMA in 2012, carried out in patients and recorded on a clinical trials registry and/or included in an EMA European Public Assessment Report (EPAR), were included. Information sources were searched between 1 May and 31 July 2014.

Outcome measures and results:

The main outcome measure was the proportion of trials for which results had been disclosed on a registry or in the scientific literature either within 12 months of the later of either first regulatory approval or trial completion, or by 31 July 2014 (end of survey). Of the completed trials associated with 23 new medicines licensed to 17 different companies in 2012, results of 90% (307/340) had been disclosed within 12 months, and results of 92% (312/340) had been disclosed by 31 July 2014.

Conclusions:

The disclosure rate within 12 months of 90% suggests the industry is now achieving disclosure in a timely manner more consistently than before. The overall disclosure rate at study end of 92% indicates that the improvement in transparency amongst company-sponsored trials has been maintained in the trials associated with new medicines approved in 2012.     

Echinacea biotechnology: advances,commercialization and future considerations

Context: Plants of the genus Echinacea (Asteraceae) are among the most popular herbal supplements on the market today. Recent studies indicate there are potential new applications and emerging markets for this natural health product (NHP).

Objective: This review aims to synthesize recent developments in Echinacea biotechnology and to identify promising applications for these advances in the industry.

Methods: A comprehensive survey of peer-reviewed publications was carried out, focusing on Echinacea biotechnology and impacts on phytochemistry. This article primarily covers research findings since 2007 and builds on earlier reviews on the biotechnology of Echinacea.

Results: Bioreactors, genetic engineering and controlled biotic or abiotic elicitation have the potential to significantly improve the yield, consistency and overall quality of Echinacea products. Using these technologies, a variety of new applications for Echinacea can be realized, such as the use of seed oil and antimicrobial and immune boosting feed additives for livestock.

Conclusions: New applications can take advantage of the well-established popularity of Echinacea as a NHP. Echinacea presents a myriad of potential health benefits, including anti-inflammatory, anxiolytic and antibiotic activities that have yet to be fully translated into new applications. The distinct chemistry and bioactivity of different Echinacea species and organs, moreover, can lead to interesting and diverse commercial opportunities.     

Standardized classification unsuitable for spontaneous reporting: the example of osteonecrosis of the jaw

Objective: This study assessed the impact of using a standardized definition of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in the analysis of a spontaneous reporting database.

Methods: All notifications of osteonecrosis of the jaw (ONJ) in the French National Pharmacovigilance Database as of 31 December 2013 were analyzed. First, we considered all reports of ONJ with bisphosphonates as BRONJ. Second, we applied the 2014 definition of BRONJ from the American Association of Oral and Maxillofacial Surgeons (AAOMS), retaining only bisphosphonates as antiresorptive medication. In the absence of any one of these criteria, or missing data, cases were not considered as BRONJ.

Results: The first analysis found 158 cases of ONJ, among which 153 were associated with bisphosphonate use. The second analysis identified only 43 cases of BRONJ (28.1%).

Conclusion: The definition of BRONJ as laid down by the AAOMS is not suitable for use in spontaneous reporting database. The use of the AAOMS definition alone should be avoided, as it leads to the exclusion of over 70% of cases. When cases of ONJ are identified, all results should be presented including confirmed and excluded cases.     

Mulberry leaves and their potential effects against cardiometabolic risks: a review of chemical compositions,biological properties and clinical efficacy

Context: Cardiometabolic risks are regarded as the crucial factors associated with type 2 diabetes (T2DM) and cardiovascular diseases (CVD). Regarding an increased attention to medicinal plants in the current healthcare system, the effects of mulberry (Morus spp., Moraceae) leaves on cardiometabolic risks have been consecutively considered in scientific research.

Objective: The present review compiles and summarizes the chemical compositions, biological properties and clinical efficacy of mulberry leaves that are related to the amelioration of cardiometabolic risks.

Methods: Published English literature from the PubMed, Science Direct and Google Scholar databases was searched by using ‘mulberry leaves’ ‘Morus spp.’, ‘hyperglycemia’, ‘hyperlipidemia’, ‘obesity’, ‘hypertension’, ‘oxidative stress’, ‘atherosclerosis’ and ‘cardiovascular diseases’ as the keywords. The relevant articles published over the past two decades were identified and reviewed.

Results: Mulberry leaves contain numerous chemical constituents. 1-Deoxynojirimycin (DNJ), phenolics and flavonoids are the prominent functional compounds. Preclinical and clinical studies showed that mulberry leaves possessed various beneficial effects against cardiometabolic risks, including antihyperglycaemic, antihyperlipidaemic, antiobesity, antihypertensive, antioxidative, anti-inflammatory, anti-atherosclerotic and cardioprotective effects.

Conclusions: Mulberry leaves could be a promising therapeutic option for modulating cardiometabolic risks. However, further investigations should be performed to substantiate the potential of mulberry leaves in practical uses.     

Shaving effects on percutaneous penetration: clinical implications

Context: Human/animal shaving biology.

Objective: To assess the effect of shaving on percutaneous penetration and skin function.

Methods: We screened 500+publications in Pub Med, Scopus, Cochrane Library and pertinent journals out of which only 17 were deemed relevant. Terms for searches included shaving and skin, percutaneous penetration and shaving, skin absorption and shaving, absorption of dyes and shaving, skin penetration, effects of shaving and absorption, shave and dyes, axillary shaving and stratum corneum, shaving and breast cancer, shaving and infections, etc.

Result: Shaving appears to have an exaggerated effect on percutaneous absorption; however, some studies do not support this evidence.

Conclusion: Shaving enhances percutaneous penetration of some chemicals; however this effect is species and chemical specific. Further investigations of chemicals of varying physio-chemical properties are mandated before a generalized theory can be promulgated.     

Cutaneous adverse reactions linked to targeted anticancer therapies bortezomib and lenalidomide for multiple myeloma: new drugs,old side effects

Context: Cutaneous toxicity is a frequent side effect of new anticancer targeted therapies. Skin reactions can severely impact the patient’s physical, psychological and social well-being and may sometimes lead to discontinuations either treatment dose reductions.

Objective: This study evaluates the impact of cutaneous adverse drug reactions (cADR) of the new therapies bortezomib and lenalidomide and presents a review of their skin side effects.

Materials and method: Type, frequency, severity, time of onset and management of cADR were collected and the medical records of all multiple myeloma patients receiving bortezomib or lenalidomide in the Hematology and Medical Oncology Institute of the University of Bologna, were analyzed.

Results: A total of 17 cADR occurred in 10 patients of 17 (58.8% of patients) treated with bortezomib: 5 rashes, 3 events of pruriginous rash, 1 purpuric rash, 2 records of mouth swelling, 1 stomatitis-mucositis, 3 cases of edema in the lower limbs, 1 patient referred pruritus and another telogen effluvium. Eight skin manifestations were due to lenalidomide in 7 patients of 25 treated (28%): 2 pruriginous rashes, 3 cases of edema, 2 records of pruritus, 1 case of stomatitis-mucositis. Three adverse events linked to bortezomib and 4 to lenalidomide forced to a complete withdrawal of the drug, while 3 reactions due to bortezomib mandated a dose reduction. Dermatological evaluation was performed only in 2 patients treated with bortezomib and 1 with lenalidomide.

Discussion: Evaluations of cADR due to bortezomib and lenalidomide were performed. There are no other reports focused on skin events in patients treated with the triple regimen velcade (bortezomib)-thalidomide-dexamethasone (VTD) up to date. Our study suggests that cutaneous toxicities, when researched by Dermatologists, are a side effect even more frequent than the reported data.

Limitations: As it is a single institute and retrospective study, ongoing cADR were rarely evaluated by dermatologists; thus, it is possible that cutaneous reactions (especially mild) may have been under reported by Hematologists and Oncologists in clinical records.

Conclusions: Even with the development of new drugs for cancer treatment, “old” cutaneous side effects may still be present, compromising patients’ quality of life. Physicians prescribing bortezomib and lenalidomide should monitor their patients for the spectrum of cADR, and they should involve dermatologists in consultations and management of these events. A multidisciplinar approach is necessary to oncologic patient in order to provide a tailored supportive clinical care.     

Conventional- versus high-dose vancomycin regimen in patients with acute bacterial meningitis: a randomized clinical trial

Objective: Efficacy of the conventional- versus high-dose vancomycin regimen in patients with acute bacterial meningitis was compared.

Methods: In a randomized clinical trial 44 patients with acute bacterial meningitis were randomly assigned to the conventional- or high-dose vancomycin groups. Clinical and laboratory parameters were used for evaluation of response to the treatment regimens.

Results: In the high-dose group, leukocytosis and fever resolved significantly faster than those in the conventional group. Furthermore, the length of hospitalization was shorter and Glasgow Coma Scale at the end of 10th day was significantly lower in the high dose compared to the conventional group. Trend of creatinine clearance changes did not differ significantly between the two groups.

Conclusion: In comparison to the conventional-dose regimen, the high-dose vancomycin regimen was associated with significantly more favorable clinical response without increase in the incidence of nephrotoxicity in patients with acute bacterial meningitis.     

Filling quality of the reports of adverse drug reactions received at the Pharmacovigilance Centre of São Paulo (Brazil): missing information hinders the analysis of suspected associations

Background: The completeness and accuracy of the reports of suspected adverse drug reactions is important in pharmacovigilance. The aim of the present study was to analyze the quality of the information included in the reports sent to the Pharmacovigilance Centre of São Paulo (Brazil).

Research design and methods: A sample of 999 reports received from January 2013 to December 2014 was selected. The quality of the filled information was evaluated according to a ‘sufficiency’ criterion to apply the Karch-Lasagna causality algorithm.

Results: There were 820 reports from manufacturers and 179 from health centres. Only 4.4% (44) were fully filled, thus allowing the adequate analysis of the causal relationship between the suspected medication and the adverse event. In 30% of the reports from manufacturers, the information about the critical variables was lacking or incomplete, preventing the adequate evaluation of the report. It was also noted that the reports’ poor filling quality was not related with less severity or with old and well-known medicines.

Conclusions: The poor quality of the information included in the reports received by this centre, especially those sent by pharmaceutical manufacturers, hampers the identification of potential safety signals. Measures to improve the quality of the reports must be urgently adopted.     

Induction of human cytochrome P450 3A4 by the irreversible myeloperoxidase inactivator PF-06282999 is mediated by the pregnane X receptor

1. 2-(6-(5-Chloro-2-methoxyphenyl)-4-oxo-2-thioxo-3,4-dihydropyrimidin-1(2H)-yl) acetamide (PF-06282999) is a member of the thiouracil class of irreversible inactivators of human myeloperoxidase enzyme and a candidate for the treatment of cardiovascular disease. PF-06282999 is an inducer of CYP3A4 mRNA and midazolam-1′-hydroxylase activity in human hepatocytes, which is consistent with PF-06282999-dose dependent decreases in mean maximal plasma concentrations (C_max) and area under the plasma concentration time curve (AUC) of midazolam in humans following 14-day treatment with PF-06282999.

2. In the present study, the biochemical mechanism(s) of CYP3A4 induction by PF-06282999 was studied. Incubations in reporter cells indicated that PF-06282999 selectively activated human pregnane X receptor (PXR). Treatment of human HepaRG cells with PF-06282999 led to ～14-fold induction in CYP3A4 mRNA and 5-fold increase in midazolam-1′-hydroxylase activity, which was nullified in PXR-knock out HepaRG cells. TaqMan® gene expression analysis of human hepatocytes treated with PF-06282999 and the prototypical PXR agonist rifampin demonstrated increases in mRNA for CYP3A4 and related CYPs that are regulated by PXR.

3. Docking studies using a published human PXR crystal structure provided insights into the molecular basis for PXR activation by PF-06282999. Implementation of PXR transactivation assays in a follow-on discovery campaign should aid in the identification of back-up compounds devoid of PXR activation and CYP3A4 induction liability.     

Cognitive defusion versus experiential avoidance in the reduction of smoking behaviour: an experimental and preliminary investigation

Background: Brief procedures that reduce smoking behaviour may be useful in reaching the many people that do not seek help for smoking addiction.

Objectives: The current study aimed to determine if one component of Acceptance and Commitment Therapy (ACT), cognitive defusion, could be useful in reducing smoking behaviour in a sample of students.

Methods: The study employed a between-subjects three-arm design. For one week, participants were asked to reduce their cigarette consumption. To aid them in their reduction, participants were randomly allocated to one of three conditions: the first received a defusion procedure, the second received an experiential avoidance procedure and a control condition received no procedure. For a second week, the instruction to reduce cigarette consumption was lifted. During both weeks participants were required to monitor their smoking behaviour via a tally diary system.

Results: The defusion condition smoked significantly less than the control condition during week one and significantly less than the control and experiential avoidance conditions during week two.

Conclusion: Results are discussed in terms of the potential utility of defusion in this domain, and the limitations of this preliminary research that would need to be addressed in future investigations.     

Postoperative nausea and vomiting – a narrative review of pathophysiology,pharmacotherapy and clinical management strategies

Introduction: Postoperative nausea and vomiting (PONV) are common complications concerning patients undergoing general anesthesia. Intensive research was performed during the last two decades in order to develop therapeutic and prophylactic strategies to prevent this complication.

Areas covered: This article reviews the pathophysiology as well as pharmacological aspects of PONV prophylaxis and treatment. Relevant strategic aspects for pharmacological prophylaxis of PONV are discussed and clinical standard operating procedures are presented.

Expert opinion: The expert opinion focuses on poor implementation of actual PONV guidelines and future considerations.     

Regulation of cytochrome P450 gene expression by ketamine: a review

Introduction: Although used as an anesthetic drug for decades, ketamine appears to have garnered renewed interest due to its potential therapeutic uses in pain therapy, neurology, and psychiatry. Ketamine undergoes extensive oxidative metabolism by cytochrome P450 (CYP) enzymes. Considerable efforts have been expended to elucidate the ketamine-induced regulation of CYP gene expression. The safety profile of chronic ketamine administration is still unclear. Understanding how ketamine regulates CYP gene expression is clinically meaningful.

Areas covered: In this article, the authors provide a brief review of clinical applications of ketamine and its metabolism by CYP enzymes. We discuss the effects of ketamine on the regulation of CYP gene expression, exploring aspects of cytoskeletal remodeling, mitochondrial functions, and calcium homeostasis.

Expert opinion: Ketamine may inhibit CYP gene expression through inhibiting calcium signaling, decreasing ATP levels, producing excessive reactive oxygen species, and subsequently perturbing cytoskeletal dynamics. Further research is still needed to avoid possible ketamine–drug interactions during long-term use in the clinic.     

Dual antiretroviral therapy for HIV infection

Introduction: For two decades, triple combinations of antiretrovirals have been the standard treatment for HIV infection. The challenges of such lifelong therapy include long-term side effects, high costs and reduced drug adherence. The recent advent of more potent and safer antiretrovirals has renewed the interest for simpler HIV regimens.

Areas covered: We discuss the pros and cons of dual antiretroviral therapies in both drug-naïve and in treatment-experienced patients with viral suppression (switch strategy).

Expert opinion: Some dual antiretroviral regimens are safe and efficacious, particularly as maintenance therapy. At this time, combinations of dolutegravir plus rilpivirine represent the best dual regimen. Longer follow-up and larger study populations are needed before supporting dolutegravir plus lamivudine. In contrast, dual therapy based on maraviroc is less effective. Although dual regimens with boosted protease inhibitors plus either lamivudine or raltegravir may be effective, they are penalized by metabolic side effects and risk for drug interactions.

The newest dual regimens could save money, reduce toxicity and spare drug options for the future. For the first time in HIV therapeutics, less can be more. Dual therapy switching has set up a new paradigm in HIV treatment that uses induction-maintenance.     

The influence of excipients on physical and pharmaceutical properties of oral lyophilisates containing a pregabalin-acetaminophen combination

Objectives: The purpose of the study was to investigate and characterize the oral lyophilisates containing the pregabalin-acetaminophen drug combination and as xcipients mannitol with microcrystalline cellulose or hydroxypropyl methylcellulose, in order to conclude upon drug-excipient interactions and their stability implications, impact of excipients on drug release and on the physicochemical and mechanical properties of the pharmaceutical formulations.

Methods: The oral tablets were made by using a Christ freeze-dryer alpha 2–4-LSC lyophilizer, and evaluated for stability, drug-excipient compatibility and homogeneity of the prepared pharmaceutical formulations. The formulations were evaluated for in vivo absorption in rabbits by histopathological exams.

Results: FTIR and thermogravimetric analyses, DLS technique, SEM and NIR-CI studies confirmed the compatibility between compounds. From the determined physical and biochemical parameters of the formulations it was established that they are stable, homogeneous, and meet the conditions for orally disintegrating tablets.

Conclusion: In the case of the investigated pharmaceutical formulations the study evidenced the assembling through physical bonds between the excipients and the ‘codrug’ complex, which do not affect the release of the bioactive compounds.     

Lidocaine 5% medicated plaster for localized neuropathic pain in thoracic surgical patients

Context: Neuropathic pain is a common and distressing symptom in thoracic surgical patients. When it consistently presents with measurable sensory changes in a circumscribed area, neuropathic pain can be diagnosed as localized neuropathic pain (LNP).

Objective: The purpose of this study was to report the efficacy of lidocaine 5% medicated plaster (Lido5%P) in the treatment of LNP in thoracic surgical patients.

Methods: We retrospectively reviewed the records of sixteen cancer and noncancer thoracic patients treated with Lido5%P for LNP. Patients had been assessed before and during treatment with standardized forms and questionnaires for pain intensity, sleep quality, drug dosages and adverse events.

Results: Treatment with Lido5%P yielded a significant and lasting improvement in pain symptomatology. In oncological patients as an add-on therapy, Lido5%P improved pain intensity and sleep quality, and delayed opioid dose escalation. In non-oncological patients as monotherapy or in association with antineuropathic drugs, Lido5%P attenuated LNP. No local or systemic adverse events were recorded.

Conclusions: Lido5%P was effective in relieving thoracic LNP, and was well tolerated.