Monitoring and assessing the safety of disease-modifying antirheumatic drugs: a West Midlands experience.

BACKGROUND: Serious adverse events may occur from the use of disease modifying antirheumatic drugs (DMARDs) used to treat rheumatoid arthritis. We describe preliminary data from a regional surveillance scheme. Our aims were to identify a broad range of potential adverse events, to identify deficiencies in care and examine the management of common events in order to improve care. METHODS: Adverse events were sought by regular postcards to clinicians in the West Midlands region of the UK. Each reported case was carefully described and the opinions of at least three peer-reviewers were sought on cause-effect relationships, the potential for prevention and the appropriateness of management. RESULTS: Forty-four serious adverse events associated with DMARD use were reported between December 1999 and October 2001. Events included eight patients with malignancies, two with pancytopenia taking methotrexate, three with septic arthritis, and two with septicaemias. Fifteen cases have been peer-reviewed in detail, so far. At least two reviewers thought that eight events were related to DMARD use and that two were preventable. Agreement between pairs of reviewers was fair or moderate (weighted kappa 0.23-0.5). DISCUSSION: We have successfully implemented a regional system for identifying potential drug-related serious adverse events. A diverse range of potential drug-related events has been seen. Early analyses have highlighted the difficulties of determining cause-effect relationships between a drug and an event.     

Clinical studies assessing immunogenicity and safety of intradermally administered influenza vaccines

Importance of the field: Human influenza A and B are major respiratory pathogens and cause high mortality and severe morbidity, especially in at-risk populations. Most of the vaccines are administered intramusculary or subcutaneously. Owing to vaccine shortage and low vaccine coverage, intradermal administration of vaccines has gained renewed interest. In addition, higher immune responses with the same quantity of antigen have been elicited with intradermal vaccine administration, offering dose-sparing capacity.

Areas covered in this review: This review summarizes the immunogenicity and safety data accumulated from influenza vaccine trials where vaccines were administered intradermally. Clinical trials performed using reduced vaccine antigen doses in healthy volunteers or in at-risk populations and target groups are discussed as well as new devices for intradermal delivery of influenza vaccines. The studies addressed in this review were identified through a MEDLINE search.

What the reader will gain: The review provides insights into the potential of intradermal vaccines to overcome hurdles such as vaccine shortage in view of mass vaccination campaigns. Moreover, evidence is provided of improved immunological responses after intradermal vaccination when new intradermal devices are being used.

Take home message: In the authors' opinion, intradermal vaccination can be considered an equally immunogenic, safe and feasible alternative to intramuscular and subcutaneous vaccination. The future looks promising because of the recent development of new intradermal vaccine delivery devices.     

Monitoring the stability of human vaccines

Postmarketing stability studies of vaccines that tend to be close to their clinical specification at the end of the expiration dating period may require enhanced annual monitoring. In addition, an early assessment of product stability prior to completion of each individual study is desired. However, predictive measures of individual lots may produce early indication of failure. In many cases, these prove to be false alarms. For such products, continued product quality after marketing should, therefore, depend less on evaluating individual observations or individual lot projections, and more on assuring that the underlying stability profile of the product as a whole has not changed. We propose a monitoring procedure and an index of the average quality of vaccine lots currently on the market. We explore the statistical properties of the index for several experimental designs for sampling of marketed lots, and we describe an optimality property of the index.     

Land-use change and emerging public health risks in New Zealand: assessing Giardia risks

Agriculture is key to New Zealand's economy with land-use conversions in response to market forces occurring regularly, like that of recent dairy intensification throughout the country. However, land-use conversion can occasionally result in unexpected and significant consequences for public health that need to be accurately estimated and subsequently managed accordingly. For example, dairy cattle have high Giardia prevalence in New Zealand and identical strains from infected humans and cattle located in the same geographical region have recently been reported. Thus, the high rates of human infections in New Zealand compared to similar socioeconomic countries caused by the waterborne pathogen Giardia are particularly concerning given the increasing dairy cattle populations on the landscape. However, the ability of traditional, evidence-based, epidemiological approaches to detect such causal relationships between land-use and Giardia infections is limited given the many possible indirect links between the two, in turn highlighting the need to develop appropriate risk assessment techniques. As such, the general requirements for and development of risk assessment frameworks to evaluate the likelihood of public health risks from waterborne pathogens are introduced and explored using Giardia in New Zealand as an example. Specifically, the importance of recent advances in Giardia-based knowledge, the incorporation of such data into existing risk assessment frameworks and the influence of remaining research gaps are each discussed for expanding currently available risk assessment tools. Not surprisingly, the availability of appropriate risk assessment tools for agencies responsible for public health and environmental management would ensure the public health risks for Giardia resulting from land-use change could be quantified holistically and strategies subsequently developed through active agency communication to minimise such risks.     

疫苗的临床前安全性评价

疫苗主要用于大规模健康人群,尤其是儿童,其安全性至关重要.临床前安全性评价是疫苗研发的重要环节之一.国家食品药品监督管理局药品审评中心于2005年公布了<预防用生物制品临床前安全性评价技术审评一般原则>,该指导原则是国内首篇用以指导疫苗临床前安全性评价技术审评工作的指导原则.文中在该指导原则的基础上,结合作者在疫苗临床前安全性评价技术审评中的认识,从疫苗临床前安全性评价的必要性、主要安全性担忧、国内外相关注册指导原则和主要技术要求方面加以综述.     

Important drug safety information on the internet: assessing its accuracy and reliability.

BACKGROUND: The Internet is becoming increasingly important as a source of health-related information, but the accuracy and reliability of information presented on the world wide web is debated. OBJECTIVE: We aimed to assess whether important, recent drug safety information is accurately reflected on Internet sites. METHODS: We evaluated whether major warnings issued by the US FDA between October 1, 2000 and September 30, 2001 on severe and life-threatening drug toxicity were mentioned 4-16 months later in the top ten web pages identified for these drugs by each of seven different search engines. We examined predictors of precise mention of the FDA warnings using logistic regressions. RESULTS: Twenty major safety warnings on 21 drugs (including three withdrawals) were eligible for the study. Among 519 different pertinent web pages retrieved (16-32 for each drug), precise mention of the safety issue was made in only 165 (31.8%). Best rates of precise mention were seen in web sites sponsored by attorneys (79.4%), in physician-oriented web pages (65.5%) and for withdrawn drugs (57.9%). In addition to these factors, better coverage of the FDA warnings was independently seen when no other adverse effects from the same organ system was mentioned (p < 0.001), while coverage was worse when there was no date on the site and web page (p = 0.020), and when the site owner could not be classified or was unknown (p = 0.014). CONCLUSIONS: Important safety warnings are inadequately covered in the majority of web pages. This deficiency creates a source of potentially harmful misinformation for health consumers.     

Methods for assessing risks of dermal exposures in the workplace

The skin as a route of entry for toxic chemicals has caused increasing concern over the last decade. The assessment of systemic hazards from dermal exposures has evolved over time, often limited by the amount of experimental data available. The result is that there are many methods being used to assess safety of chemicals in the workplace. The process of assessing hazards of skin contact includes estimating the amount of substance that may end up on the skin and estimating the amount that might reach internal organs. Most times, toxicology studies by the dermal route are not available and extrapolations from other exposure routes are necessary. The hazards of particular chemicals can be expressed as "skin notations", actual exposure levels, or safe exposure times. Characterizing the risk of a specific procedure in the workplace involves determining the ratio of exposure standards to an expected exposure. The purpose of this review is to address each of the steps in the process and describe the assumptions that are part of the process. Methods are compared by describing their strengths and weaknesses. Recommendations for research in this area are also included.     

肠球菌属药物的潜在风险与应用安全

肠球菌属益生菌药物应用广泛,其致病性及对耐药性的传递值得引起关注。本文综合相关文献,初步阐述其潜在风险及安全应用需要注意的易感群体及关键因素。目前相关药物在患者适用性评估和药品警示方面的不足有待改善。     

Regulating and assessing risks of cholinesterase-inhibiting pesticides: divergent approaches and interpretations

This document presents a revised framework for conducting worker and dietary risk assessments for less-than-lifetime exposures to organophosphate or carbamate pesticides based on red blood cell (RBC) or brain acetylcholinesterase (AChE) inhibition or the presence of clinical signs and symptoms. The proposals for appropriate uncertainty factors are based on the biological significance of the cholinesterase (ChE) inhibition noted at the lowest-observed-effect level (LOEL) and the degree of uncertainty in the extrapolation between human and animal data. An extensive evaluation of industry data, not previously summarized, and the available literature indicate that the following risk assessment principles are supportable and protective of human health: Plasma ChE inhibition is not an adverse effect, and therefore should not be utilized in risk assessments. Red blood cell AChE is not associated with the nervous system and inhibition is not per se an adverse (neurotoxic) effect. When available, cholinergic effects or brain AChE inhibition data should take precedence over RBC AChE for determining no-observed-effect levels (NOELs). When available, human RBC AChE inhibition or cholinergic effects data should take precedence over animal data for determining NOELs. Due to the lack of adversity associated with inhibition of RBC AChE, the use of a 10-fold (10x) uncertainty factor from the NOEL is adequate when RBC AChE inhibition data from either animal or human studies are used to assess human risk. Due to greater potential for adversity, NOELs for brain AChE inhibition and cholinergic effects identified in animal studies should receive a default uncertainty factor of 100x; lower uncertainty factors may be used on a case-by-case basis. NOELs based on cholinergic effects noted in human studies should only require a 10x uncertainty factor, since an interspecies extrapolation factor from animals to humans is unnecessary. For RBC and brain AChE activity the threshold for defining a NOEL should be less than or equal to 20% difference from control activity in all species. For risk assessment purposes, duration and route of the study should reflect the expected duration and route of exposure for humans (i.e., a 21-d or 28-d dermal study for subchronic occupational dermal exposure assessment). When dermal data are not available, a subchronic oral toxicity study and an appropriate dermal penetration factor should be used. A general default of 10% absorption should be used, analogous to the United Kingdom and German exposure models that are widely used in Europe. The recommendations in this document are generally consistent with current risk assessment procedures used by Canada, the European Community (EC), and the United Kingdom (UK).     

Exposure to combinations of substances: a system for assessing health risks

Combined exposures may be categorised as specified combinations or mixtures of substances, depending on composition and exposure scenario. The major characteristic of a specified combination is known composition and that of a mixture simultaneous exposure. A framework was developed as a guide for safety evaluation of combined exposures. This framework offers the possibility to evaluate mixtures as a single entity, or as a number of fractions or individual constituents. The evaluation of specified combinations will often focus on the individual components. To reduce the safety evaluation of complex exposures to manageable proportions, the “top n” and “pseudo top n” approaches were introduced, n representing the n most “risky” chemicals or groups of chemicals, respectively. To select the best method, the framework should always be walked through in its entirety, considering all options. The Mumtaz–Durkin weight-of-evidence approach is included as a prioritization instrument for combined exposures. It is based on hazard indices supplemented with qualitative and quantitative weighting and interaction factors.     

Treating inflammatory bowel disease during pregnancy: risks and safety of drug therapy.

The safety of drug therapy for inflammatory bowel disease during pregnancy is an important clinical concern. Current available information is largely derived from animal studies and clinical experience among patients with inflammatory bowel disease and autoimmune disorders and organ transplant recipients. However, these data are confounded by various factors including difficulty projecting the results of animal studies to humans, methodological deficiencies of some studies, insufficient experience with certain agents, difficulty distinguishing the fetal effects of underlying disease from drug therapy and a need to consider the impact of background rates of adverse fetal outcomes which apply to all pregnancies. In inflammatory bowel disease, the effects of active inflammation on the fetus are believed to be more harmful than those of drug treatment, and therapy is often justified to induce or maintain remission during pregnancy. The choice of appropriate treatment is determined by the severity of the disease and the potential for drug toxicity. No causal relationship has been established between exposure to sulfasalazine or other 5-aminosalicylic acid drugs and the development of congenital malformations. These drugs may be used with relative safety during pregnancy and lactation. Considerable experience with corticosteroids have shown them to pose very small risk to the developing fetus. Current evidence indicates that maternal use of azathioprine is not associated with an increased risk of congenital malformations, though impaired fetal immunity, growth retardation or prematurity is occasionally observed. Preliminary evidence derived from patients with inflammatory bowel disease show no significant fetal toxicity following first trimester exposure to mercaptopurine, though its elective use in pregnancy is controversial. Cyclosporin is not teratogenic, but may be associated with growth retardation and prematurity. Pregnancy should be avoided in women treated with methotrexate because of its known abortifacient effects and risk of causing typical malformations. Although treatment with metronidazole or ciprofloxacin for short durations appear to be devoid of adverse fetal reactions, the effect of prolonged exposure as required in Crohn's disease remains unknown.     

他汀类药物的安全性风险评价

他汀类药物是最广泛的可用药物治疗降低胆固醇水平,并控制其发展的处方药。所有的他汀类药物,如阿托伐他汀、氟伐他汀、洛伐他汀、匹伐他汀、普伐他汀、瑞舒伐他汀和辛伐他汀可用于心血管疾病事件的预防。众所周知,在治疗过程中一些服用他汀类药物的患者出现不良反应,如肝损害、癌症的风险和骨骼肌损害。因此,认识他汀类药物的安全性风险是很重要的。根据发表的他汀类药物的临床研究文献数据,分析和认识这类药物的安全性、不良反应及毒性的风险,并简要介绍了由美国心脏协会和美国心脏病学院基于4年评述而制定的2013年他汀类降胆固醇药物新使用指南。     

Monitoring the safety of licensed medicines

The withdrawal of the selective cyclooxygenase 2 inhibitor rofecoxib owing to cardiovascular side effects ignited debate about the need for major changes to current mechanisms for post-marketing surveillance (PMS) of drug safety. Here, we discuss the current mechanisms, whether they are being used appropriately, and consider the need for changes to regulatory systems.