Post-approval quality-related regulatory actions for biopharmaceuticals approved in the European Union and the United States between 1995 and 2019

The quality of biopharmaceuticals is carefully monitored by manufacturers and regulators to ensure safety and efficacy throughout the entire product life cycle. Quality defects can lead to post-approval regulatory actions (RAs) to inform healthcare professionals (HCPs). The present study identified quality-related RAs for biopharmaceuticals approved in the European Union and United States between 1995 and 2019. Quality-related RAs were issued due to various quality defects and required different actions by HCPs. The quality defects were not identified due to a negative impact on efficacy and/or safety, which is reassuring. The findings reflect the capability of the stringent regulatory system and quality control to capture and counter various quality defects before the affected product and batches can harm patients.

Donor Commitments and Disbursements for Sexual and Reproductive Health Aid in Kenya, Tanzania, Uganda and Zambia

Background: Sexual and Reproductive Health and Rights (SRHR) investments are critical to people's well-being. However, despite the demonstrated returns on investments, underfunding of SRHR still persists. The objective of this study was to characterize donor commitments and disbursements to SRH aid in four sub-Saharan countries of Kenya, Tanzania, Uganda and Zambia and to compare trends in donor aids with SRH outcome and impact indicators for each of these countries. Methods: The study is a secondary analysis of data from the Organization for Economic Co-operation and Development's Assistance creditor reporting system and SRH indicator data from the Global Health Observatory and country demographic health surveys for a 16-year period (2002-2017). We downloaded and compared commitments to disbursements of all donors for population policies, programs and reproductive health for the four African countries. SRH indicators were stratified into health facility level process/outcome indicators (modern contraceptive prevalence rate, unmet need for family planning, antenatal care coverage and skilled birth attendance) and health impact level indicators (maternal mortality ratio, newborn mortality rate, infant mortality rate and under five mortality rate). Results: Donor commitments for SRH aid grew on average by 20% while disbursements grew by 21% annually between 2002 and 2017. The overall disbursement rate was 93%. Development Assistance Cooperation (DAC) countries donated the largest proportion (79%) of aid. Kenya took 33% of total aid, followed by Tanzania 26%, Uganda 23% and then Zambia (18%). There was improvement in all SRH outcome and impact indicators, but not enough to meet targets. Conclusion: Donor aid to SRH grew over time and in the same period indicators improved, but improvement remained slow. Unpredictability and insufficiency of aid may be disruptive to recipient country planning. Donors and low- and middle-income countries should increase funding in order to meet global SRHR targets.

Trends in access to anti-malarial treatment in the formal private sector in Uganda: an assessment of availability and affordability of first-line anti-malarials and diagnostics between 2007 and 2018

Background

Malaria is the single largest cause of illness in Uganda. Since the year 2008, the Global Fund has rolled out several funding streams for malaria control in Uganda. Among these are mechanisms aimed at increasing the availability and affordability of artemisinin-based combination therapy (ACT). This paper examines the availability and affordability of first-line malaria treatment and diagnostics in the private sector, which is the preferred first point of contact for 61% of households in Uganda between 2007 and 2018.

Methods

Cross-sectional surveys were conducted between 2007 and 2018, based on a standardized World Health Organization/Health Action International (WHO/HAI) methodology adapted to assess availability, patient prices, and affordability of ACT medicines in private retail outlets. A minimum of 30 outlets were surveyed per year as prescribed by the standardized methodology co-developed by the WHO and Health Action International. Availability, patient prices, and affordability of malaria rapid diagnostic tests (RDTs) was also tracked from 2012 following the rollout of the test and treat policy in 2010. The median patient prices for the artemisinin-based combinations and RDTs was calculated in US dollars (USD). Affordability was assessed by computing the number of days’ wages the lowest-paid government worker (LPGW) had to pay to purchase a treatment course for acute malaria.

Results

Availability of artemether/lumefantrine (A/L), the first-line ACT medicine, increased from 85 to100% in the private sector facilities during the study period. However, there was low availability of diagnostic tests in private sector facilities ranging between 13% (2012) and 37% (2018). There was a large reduction in patient prices for an adult treatment course of A/L from USD 8.8 in 2007 to USD 1.1 in 2018, while the price of diagnostics remained mostly stagnant at USD 0.5. The affordability of ACT medicines and RDTs was below one day’s wages for LPGW.

Conclusions

Availability of ACT medicines in the private sector medicines retail outlets increased to 100% while the availability of diagnostics remained low. Although malaria treatment was affordable, the price of diagnostics remained stagnant and increased the cumulative cost of malaria management. Malaria stakeholders should consolidate the gains made and consider the inclusion of diagnostic kits in the subsidy programme.

Comparison of consistency and complementarity of reporting biosimilar quality attributes between regulatory and scientific communities: An adalimumab case study

Biosimilar approval relies on the comparability of quality attributes (QAs), for which information can be derived from regulatory or scientific communities. Limited information is known about whether these sources are consistent with or complementary to each other. The consistency and complementarity of QA reporting in biosimilarity assessments for adalimumab biosimilars approved by the European Medicines Agency in European public assessment reports (EPARs) and scientific publications was assessed. A classification of 77 different QAs (53 structural and 24 functional attributes) was used to assess the types of and information on QAs reported. Six adalimumab biosimilars were analyzed, for which the number of QAs reported in EPARs and publications varied (range = 47 [61%]-60 [78%]). The proportion of QAs consistently reported in both sources varied (range = 28%-75%) among biosimilars; functional QAs (mean = 21 QAs [88%]; range = 19-23) were more consistently reported than structural QAs (mean = 33 QAs [62%]; range = 27-34). The EPARs frequently reported biosimilarity interpretation without providing test results (9-57 QAs in EPARs versus 0-8 QAs in publications), whereas publications frequently reported both test results and interpretations (13-40 QAs in publications versus 0-3 QAs in EPARs). Both sources provided information on the biosimilarity of QAs in a complementary manner and the same biosimilarity interpretation of test results for reported QAs (mean = 90%; range = 78%-100%), with a small discrepancy in biosimilarity interpretations of a few clinically relevant QAs related to post-translation modifications and biological activity. Comprehensive reporting of QAs can contribute to an improved understanding of the role of structural and functional attributes in establishing biosimilarity and the mechanism of action of biological substances in general.

Intensive Monitoring Studies for Assessing Medicines: A Systematic Review

Introduction: Intensive monitoring (IM) is one of the methods of post-marketing active surveillance based upon event monitoring, which has received interest in the current medicines regulatory landscape. For a specific period of time, IM involves primary data collection and is actively focused on gathering longitudinal information, mainly safety, since the first day of drug use.

Objectives: To describe IM systems and studies' data published over 11-years period (2006–2016). Specifically, we reviewed study population/event surveillance, methodological approaches, limitations, and its applications in the real-world evidence generation data.

Methods: We completed a systematic search of MEDLINE and EMBASE to identify studies published from 2006 to 2016, that used IM methodology. We extracted data using a standardized form and results were analyzed descriptively. The methodological quality of selected studies was assessed using the modified Downs and Black checklist.

Results: From 1,400 screened citations, we identified 86 papers, corresponding to 69 different studies. Seventy percent of reviewed studies corresponded to established IM systems, of which, more than half were prescription event monitoring (PEM) and modified-PEM. Among non-established IM systems, vaccines were the most common studied drugs (n = 14). The median cohort size ranged from 488 (hospitals) to 10,479 (PEM) patients. Patients and caregivers were the event data source in 39.1% of studies. The mean overall quality score was similar between established and non-established IM.

Conclusions: Over the study period, IM studies were implemented in 26 countries with different maturity levels of post-marketing surveillance systems. We identified two major limitations: only 20% of studies were conducted at hospital-level, which is a matter of concern, insofar as healthcare systems are facing a lack of access to new medicines at ambulatory care level. Additionally, IM access to data of drug exposure cohorts, either at identification or at follow-up stages, could somehow constitute a barrier, given the complexity of managerial, linkable, and privacy data issues.

Evidence Synthesis in Harm Assessment of Medicines Using the Example of Rosiglitazone and Myocardial Infarction

The current system of harm assessment of medicines has been criticized for relying on intuitive expert judgment. There is a call for more quantitative approaches and transparency in decision-making. Illustrated with the case of cardiovascular safety concerns for rosiglitazone, we aimed to explore a structured procedure for the collection, quality assessment, and statistical modeling of safety data from observational and randomized studies. We distinguished five stages in the synthesis process. In Stage I, the general research question, population and outcome, and general inclusion and exclusion criteria are defined and a systematic search is performed. Stage II focusses on the identification of sub-questions examined in the included studies and the classification of the studies into the different categories of sub-questions. In Stage III, the quality of the identified studies is assessed. Coding and data extraction are performed in Stage IV. Finally, meta-analyses on the study results per sub-question are performed in Stage V. A Pubmed search identified 30 randomized and 14 observational studies meeting our search criteria. From these studies, we identified 4 higher level sub-questions and 4 lower level sub-questions. We were able to categorize 29 individual treatment comparisons into one or more of the sub-question categories, and selected study duration as an important covariate. We extracted covariate, outcome, and sample size information at the treatment arm level of the studies. We extracted absolute numbers of myocardial infarctions from the randomized study, and adjusted risk estimates with 95% confidence intervals from the observational studies. Overall, few events were observed in the randomized studies that were frequently of relatively short duration. The large observational studies provided more information since these were often of longer duration. A Bayesian random effects meta-analysis on these data showed no significant increase in risk of rosiglitazone for any of the sub-questions. The proposed procedure can be of additional value for drug safety assessment because it provides a stepwise approach that guides the decision-making in increasing process transparency. The procedure allows for the inclusion of results from both randomized an observational studies, which is especially relevant for this type of research.

Risk of infections in patients with gout: a population-based cohort study

To investigate the risk of various types of infections (pneumonia and urinary tract infection (UTI)), and infection-related mortality in patients with gout compared with population-based controls. A retrospective cohort study was conducted using data from the UK Clinical Practice Research Datalink (CPRD). All patients with a first diagnosis of gout and aged >40 years between January 1987-July 2014, were included and matched with up to two controls. Time-varying Cox proportional hazards models were used to estimate the risk of infections and mortality. 131,565 patients and 252,763 controls (mean age: 64 years, 74% males, mean follow-up of 6.7 years) were included in the full cohort. After full statistical adjustment, the risk of pneumonia was increased (adj. HR 1.27, 95% CI 1.18 to 1.36), while the risk of UTI (adj. HR 0.99, 95% CI 0.97 to 1.01) was similar in patients compared to controls. No differences between patients and controls were observed for infection-related mortality due to pneumonia (adj. HR 1.03, 95% CI 0.93 to 1.14) or UTI (adj. HR 1.16, 95% CI 0.98 to 1.37). In conclusion, patients with gout did not have decreased risks of pneumonia, UTI or infection-related mortality compared to population-based controls.

Are age-appropriate antibiotic formulations missing from the WHO list of essential medicines for children? A comparison study

OBJECTIVE

There is a global call for formulations, which are better suited for children of different age categories and in a variety of settings. One key public health area of interest is age-appropriate paediatric antibiotics. We aimed to identify clinically relevant paediatric formulations of antibiotics listed on pertinent formularies that were not on the WHO Essential Medicines List for Children (EMLc).

METHODS

We compared four medicines lists versus the EMLc and contrasted paediatric antibiotic formulations in relation to administration routes, dosage forms and/or drug strengths. The additional formulations on comparator lists that differed from the EMLc formulations were evaluated for their added clinical values and costs.

RESULTS

The analysis was based on 26 EMLc antibiotics. Seven oral and two parenteral formulations were considered clinically relevant for paediatric use. Frequently quoted benefits of oral formulations included: filling the gap of unmet therapeutic needs in certain age/weight groups (phenoxymethylpenicillin and metronidazole oral liquids, and nitrofurantoin capsules), and simplified administration and supply advantages (amoxicillin dispersible tablets, clyndamycin capsules, cloxacillin tablets, and sulfamethoxazole+trimethoprim tablets). Lower doses of ampicillin and cefazolin powder for injection could simplify the dosing in newborns and infants, reduce the risk of medical errors, and decrease the waste of medicines, but may target only narrow age/weight groups.

CONCLUSIONS

The identified additional formulations of paediatric antibiotics on comparator lists may offer clinical benefits for low-resource settings, including simplified administration and increased dosing accuracy. The complexity of both procuring and managing multiple strengths and formulations also needs to be considered.

Health system productivity change in Zambia: A focus on the child health services

Efficiency and productivity improvement have become central in global health debates. In this study, we explored productivity change, particularly the contribution of technological progress and efficiency gains associated with improvements in child survival in Zambia (population 15 million). Productivity was measured by applying the Malmquist productivity index on district-level panel data. The effect of socioeconomic factors was further analyzed by applying an ordinary least squares regression technique. During 2004-2009, overall productivity in Zambia increased by 5.0 per cent, a change largely attributed to technological progress rather than efficiency gains. Within-country productivity comparisons revealed wide heterogeneity in favor of more urbanized and densely populated districts. Improved cooking methods, improved sanitation, and better educated populations tended to improve productive gains, whereas larger household size had an adverse effect. Addressing such district-level factors and ensuring efficient delivery and optimal application of existing health technologies offer a practical pathway for further improving population health.

Relative effectiveness assessments of oncology medicines for pricing and reimbursement decisions in European countries

BACKGROUND

There is a debate on the added clinical value of new, expensive, anticancer treatments. Among European decision makers, the relevance of commonly used end points in trials, especially overall survival (OS), progression-free survival (PFS) and quality of life (QoL), varies, leading to the available evidence being valued differently. This research studies the extent to which the value of end points for cancer medicines differs among European decision makers.

METHODS

We compared guidelines and relative effectiveness assessments (REAs) of medicines for pricing or reimbursement decisions in England, France, Germany, The Netherlands, Poland, and Scotland. Anticancer medicines that received marketing authorization in Europe between 2011 and 2013 with at least four available national REAs were evaluated. A total of 79 REAs were included.

RESULTS

Health technology assessment (HTA) guidelines indicate a preference for clinically and patient relevant end points such as OS and QoL above surrogate end points. Most guidelines do not specify whether PFS is considered a surrogate or patient-relevant end point. The number of REAs included per jurisdiction varied between 7 (The Netherlands) and 18 (Germany). OS data were included in all REAs and were the preferred end point by HTA agencies, but these data were not always mature or robust. QoL data are included in only 54% of the REAs, with a limited impact on the recommendations. PFS data are included in 70% of the REAs, but the extent to which HTA agencies find PFS relevant varies.

CONCLUSIONS

European decision-making on relative effectiveness of anticancer medicines is affected by a gap in requested versus available clinical evidence, mainly because the regulator is willing to accept some degree of clinical uncertainty. A multi-stakeholder debate would be essential to align concrete robust evidence requirements in oncology and a collectively shared definition for relevant clinical benefit, which will benefit patients and society in general.

Smoke-free legislation and the incidence of paediatric respiratory infections and wheezing/asthma: interrupted time series analyses in the four UK nations

We investigated the association between introduction of smoke-free legislation in the UK (March 2006 for Scotland, April 2007 for Wales and Northern Ireland, and July 2007 for England) and the incidence of respiratory diseases among children. We extracted monthly counts of new diagnoses of wheezing/asthma and RTIs among children aged 0–12 years from all general practices in the Clinical Practice Research Datalink during 1997–2012. Interrupted time series analyses were performed using generalised additive mixed models, adjusting for underlying incidence trends, population size changes, seasonal factors, and pandemic influenza, as appropriate. 366,642 new wheezing/asthma diagnoses and 4,324,789 RTIs were observed over 9,536,003 patient-years. There was no statistically significant change in the incidence of wheezing/asthma after introduction of smoke-free legislation in England (incidence rate ratio (IRR) 0.94, 95% CI 0.81–1.09) or any other UK country (Scotland: IRR 0.99, 95% CI 0.83–1.19; Wales: IRR 1.09, 95% CI 0.89–1.35; Northern Ireland: IRR 0.96, 95% CI 0.76–1.22). Similarly no statistically significant changes in RTI incidence were demonstrated (England: IRR 0.95, 95% CI 0.86–1.06; Scotland: IRR 0.96, 95% CI 0.83–1.11; Wales: IRR 0.97, 95% CI 0.86–1.09; Northern Ireland: IRR 0.90, 95% CI 0.79–1.03). There were no demonstrable reductions in the incidence of paediatric wheezing/asthma or RTIs following introduction of smoke-free legislation in the UK.

Safety review in 10,008 users of lansoprazole in daily practice

Purpose-Soon after the introduction of the proton pump inhibitor, lansoprazole, a 4-year observational follow-up study was started to evaluate the safety of this drug in naturally-occurring groups of patients in The Netherlands. Results of this study were compared with clinical trial data and the limited published data from observational studies.Methods- prospective, observational study in which patients with a new episode of lansoprazole use were followed during the medication period for a maximum of 2 years. All (adverse) events during use were documented by the prescriber, irrespective of possible association with lansoprazole therapy.Results- total of 805 general practitioners (GPs) and 266 specialists provided a total of 10,008 lansoprazole users with a broad range of diagnoses. Of all patients, 17.4% reported one or more adverse events. The profile and frequency of reported adverse events was consistent with results from clinical trials and other observational studies. The most frequently reported adverse events were diarrhoea, headache, nausea, skin disorders, dizziness and generalized abdominal pain/cramps. There was no new evidence of rare adverse events. Furthermore, no lansoprazole-related unlabelled adverse events of clinical significance were recorded.Conclusions- Although the patterns of use of lansoprazole in daily practice deviated to some extent from the diagnoses in the information leaflet, lansoprazole was found to have a highly acceptable safety profile in this large naturally-occurring group of users. Reporting rates were higher soon after introduction of lansoprazole before falling to a lower stable level. Copyright (c) 2000 John Wiley & Sons, Ltd.

Relative effectiveness assessment of pharmaceuticals: similarities and differences in 29 jurisdictions

OBJECTIVE

Assessment of the effectiveness compared with alternative treatment(s) plays an important role in many jurisdictions in determining the reimbursement status of pharmaceuticals. This type of assessment is often referred to as a relative effectiveness assessment (REA) and is carried out by many jurisdictions. Increased sharing of information across jurisdictions may save costs and reduce duplication. The objective of this study was to explore the main similarities and differences in the major methodological aspects of REA in multiple jurisdictions.

METHODS

Data were gathered with a standardized data extraction form by searching publicly available information and by eliciting information from representatives at relevant organizations.

RESULTS

Of the initially included 35 jurisdictions, data were gathered for 29 jurisdictions. There seem to be substantial similarities on the choice of the comparator, the role of indirect comparisons, and preferred end points in REAs (except for the use of health state utilities). Jurisdictions, however, differ in whether effectiveness (usual circumstances of health care practice) is estimated in case no (comparative) effectiveness data are available and how this is done.

CONCLUSION

Some important methodological aspects for REA are approached in a similar way in many jurisdictions, indicating that collaboration on assessments may be feasible. Enhanced collaboration in the development of methods and best practices for REA between jurisdictions will be a necessary first step. Important topics for developing best practice are indirect comparisons and how to handle the gap between efficacy and effectiveness data in case good quality comparative effectiveness data are not yet available at the time of reimbursement decisions.

Pharmacogenetics in randomized controlled trials: considerations for trial design

Pharmacogenetic analyses of clinical trials aim to either detect whether a subgroup of patients identified by genetic characteristics responds differently to the treatment or to verify whether a proposed genotype-guided treatment is beneficial over standard care. This article describes three different trial designs, differing in the timing of randomization and genotyping. Each design has its own advantages, and the objectives and conditions under which each one is most suited are discussed.

Use of dipeptidyl peptidase-4 inhibitors and the reporting of infections: a disproportionality analysis in the World Health Organization VigiBase

OBJECTIVE

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of antidiabetic drugs. They inactivate incretin hormones but also have many other effects throughout the body, among which are effects on the immune system. This might result in an increased infection risk. This study assessed the association between use of DPP-4 inhibitors and the reporting of infections.

RESEARCH DESIGN AND METHODS

A nested case-control was conducted using VigiBase, the World Health Organization-Adverse Drug Reactions (WHO-ADR) database. The base cohort consisted of ADRs for antidiabetic drugs (Anatomical Therapeutic Chemical code A10). Cases were defined as ADRs of infection according to the Medical Dictionary for Regulatory Activities (MedDRA) classification system. All other ADRs were considered controls. Reporting odds ratios (RORs) were calculated to estimate the strength of the association between different classes of antidiabetic drugs and the reporting of infections.

RESULTS

We identified 305,415 suspected ADRs involving antidiabetic drugs in 106,469 case reports, of which 8,083 involved DPP-4 inhibitors monotherapy. Overall, the reporting of infections was higher for patients using DPP-4 inhibitors compared with users of biguanides (ROR 2.3 [95% CI 1.9-2.7]). Reporting of upper respiratory tract infections (ROR 12.3 [95% CI 8.6-17.5]) was significantly associated with use of DPP-4 inhibitors.

CONCLUSIONS

This study indicates an increased reporting of infections, in particular upper respiratory tract infections, for users of DPP-4 inhibitors compared with users of other antidiabetic drugs. However, the limitations of spontaneous reporting systems (e.g., underreporting, the Weber-effect, reporting bias) should be taken into account. Therefore, further research is needed to evaluate this suspicion and the underlying mechanism.

Regulatory scientific advice in drug development: does company size make a difference?

Purpose

To assess whether the content of Scientific Advice (SA) questions addressed to a national drug regulatory agency is associated with company size. This may help to increase understanding about the knowledge, strategic, and regulatory gaps companies face during drug development.

Methodology

A cross-sectional analysis was performed of SA provided by the Dutch Medicines Evaluation Board (MEB) in 2006–2008. Definition of company size was based on ranking by total revenues (Scrip’s Pharmaceutical Company League Tables 2008). The content of each SA question was scored according to predefined domains (quality, nonclinical, clinical, regulatory, and product information), their subdomains (e.g., efficacy), and a selection of additional content variables (e.g., endpoints, choice of active comparator).

Results

In total, 201 SA documents including 1,087 questions could be identified. Small, medium-sized, and large companies asked for SA 110 (54.7%), 40 (19.9%), and 51 (25.4%) times, respectively. Clinical questions were asked most often (65.9%), mainly including efficacy (33.2%) and safety questions (24.0%). The most frequent topics were overall efficacy and safety strategy. Small companies asked quality and nonclinical questions more often (P < 0.001) and clinical questions less frequently than large companies (P = 0.004). Small companies asked significantly more clinical questions about pharmacokinetics, including bioequivalence, than medium-sized and large companies (P < 0.001).

Conclusion

The array of topics addressed in SA provides an interesting outlook on what industry considers to be still unresolved in drug development and worthwhile to discuss with regulators. Company size is associated with the content of SA questions. MEB advice accommodates both innovative and noninnovative drug development.

A comparison of cost effectiveness using data from randomized trials or actual clinical practice: selective cox-2 inhibitors as an example

BACKGROUND

Data on absolute risks of outcomes and patterns of drug use in cost-effectiveness analyses are often based on randomised clinical trials (RCTs). The objective of this study was to evaluate the external validity of published cost-effectiveness studies by comparing the data used in these studies (typically based on RCTs) to observational data from actual clinical practice. Selective Cox-2 inhibitors (coxibs) were used as an example.

METHODS AND FINDINGS

The UK General Practice Research Database (GPRD) was used to estimate the exposure characteristics and individual probabilities of upper gastrointestinal (GI) events during current exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) or coxibs. A basic cost-effectiveness model was developed evaluating two alternative strategies: prescription of a conventional NSAID or coxib. Outcomes included upper GI events as recorded in GPRD and hospitalisation for upper GI events recorded in the national registry of hospitalisations (Hospital Episode Statistics) linked to GPRD. Prescription costs were based on the prescribed number of tables as recorded in GPRD and the 2006 cost data from the British National Formulary. The study population included over 1 million patients prescribed conventional NSAIDs or coxibs. Only a minority of patients used the drugs long-term and daily (34.5% of conventional NSAIDs and 44.2% of coxibs), whereas coxib RCTs required daily use for at least 6-9 months. The mean cost of preventing one upper GI event as recorded in GPRD was US$104k (ranging from US$64k with long-term daily use to US$182k with intermittent use) and US$298k for hospitalizations. The mean costs (for GPRD events) over calendar time were US$58k during 1990-1993 and US$174k during 2002-2005. Using RCT data rather than GPRD data for event probabilities, the mean cost was US$16k with the VIGOR RCT and US$20k with the CLASS RCT.

CONCLUSIONS

The published cost-effectiveness analyses of coxibs lacked external validity, did not represent patients in actual clinical practice, and should not have been used to inform prescribing policies. External validity should be an explicit requirement for cost-effectiveness analyses.

Global strategies to reduce the price of antiretroviral medicines: evidence from transactional databases

OBJECTIVE

To estimate the impact of global strategies, such as pooled procurement arrangements, third-party price negotiation and differential pricing, on reducing the price of antiretrovirals (ARVs), which currently hinders universal access to HIV/AIDS treatment.

METHODS

We estimated the impact of global strategies to reduce ARV prices using data on 7253 procurement transactions (July 2002-October 2007) from databases hosted by WHO and the Global Fund to Fight AIDS, Tuberculosis and Malaria.

FINDINGS

For 19 of 24 ARV dosage forms, we detected no association between price and volume purchased. For the other five ARVs, high-volume purchases were 4-21% less expensive than medium- or low-volume purchases. Nine of 13 generic ARVs were priced 6-36% lower when purchased under the Clinton Foundation HIV/AIDS Initiative (CHAI). Fifteen of 18 branded ARVs were priced 23-498% higher for differentially priced purchases compared with non-CHAI generic purchases. However, two branded, differentially priced ARVs were priced 63% and 73% lower, respectively, than generic non-CHAI equivalents.

CONCLUSION

Large purchase volumes did not necessarily result in lower ARV prices. Although current plans for pooled procurement will further increase purchase volumes, savings are uncertain and should be balanced against programmatic costs. Third-party negotiation by CHAI resulted in lower generic ARV prices. Generics were less expensive than differentially priced branded ARVs, except where little generic competition exists. Alternative strategies for reducing ARV prices, such as streamlining financial management systems, improving demand forecasting and removing barriers to generics, should be explored.

Psychiatric and cardiovascular comorbidities in patients with diabetes mellitus starting antiobesity drugs

The aim of the study was to assess whether the baseline risk of psychiatric and cardiovascular disease in patients with diabetes mellitus differs between those starting to use antiobesity drugs and those not starting to use these drugs. A retrospective nested case-control study within the General Practice Research Database (1987-2002) was done. The cohort included all patients with diabetes mellitus (n = 141,164). Information on patient characteristics (general, cardiovascular, and psychiatric characteristics) was extracted from the medical records. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. A total of 511 patients starting to use antiobesity drugs (cases) and 3,065 controls were included in the study cohort. Starters were younger and more frequently female. Of the starters, 91.8% did not receive any dietary advice before starting treatment. Depression (in the year before index date) was associated with the use of antiobesity drugs (OR 2.2; 95% CI 1.7-2.8), as was anxiety (OR 1.6; 95% CI 1.1-2.4). Of the cases, 25.2% had multiple cardiovascular risk factors (>4) compared to 19.0% of the controls. The baseline risk for psychiatric disorders and cardiovascular disease was found to be higher in patients with diabetes mellitus starting to use antiobesity drugs compared to patients with diabetes mellitus not starting such treatment.

Beliefs about medicines predict refill adherence to inhaled corticosteroids

OBJECTIVE

Despite the importance of the chronic use of inhaled corticosteroids (ICS) in maintaining asthma control, reported adherence varies between 40% and 60%. The Beliefs about Medicines Questionnaire (BMQ) has been shown to correlate with self-reported adherence. The aim of this study is to investigate whether beliefs about ICS (necessity and concerns), as measured by the BMQ, relate to adherence objectively measured by prescription-refill records.

METHODS

In a cross-sectional study of patients aged 18-45 years who filled at least two ICS prescriptions in 11 community pharmacies in The Netherlands, perceptions of ICS were assessed using the BMQ. Additionally, self-reported adherence was assessed using the Medication Adherence Report Scale. ICS prescription-refill adherence rates for a 12-month period prior to the survey were obtained from automated pharmacy dispensing records. Four attitudinal groups were defined using the necessity and concerns constructs. Statistical tests were used to examine associations between ICS adherence (assessed by subjective self-report and objective pharmacy records), specific beliefs about and attitudes towards ICS, and more general beliefs about pharmaceuticals.

RESULTS

Questionnaires were returned by 238 patients (51.1%). Both self-reported adherence (r=.38) and adherence by pharmacy records (rho=0.32) correlated with ICS necessity beliefs and concerns. Patients defined as skeptical, indifferent, ambivalent, or accepting, on the basis of these constructs, differed with respect to both their attitudes towards medicines in general and their adherence to medication.

CONCLUSIONS

Patients' beliefs about ICS correlate not only with adherence by self-report but also with a more objective measure of medication adherence calculated by pharmacy dispensing records. The necessity-concerns constructs offer a potentially useful framework to help clinicians elicit key treatment beliefs influencing adherence to ICS.

Dyspepsia in chronic psychiatric patients

INTRODUCTION

We report on dyspeptic complaints among patients hospitalized in the long-stay ward of a general psychiatric hospital.

METHODS

A representative sample of the patients was interviewed using a structured questionnaire.

RESULTS

Eighty percent of the patients reported one or more symptoms of dyspepsia, and 68 % reported symptoms of reflux-like dyspepsia.

CONCLUSION

Significant positive associations were found for dyspepsia complaints and clozapine (OR = 3.4), laxatives (OR = 4.4), and heavy smoking (OR = 2.3).

Initial benzodiazepine use and improved health-related quality of life

OBJECTIVE

The health-related quality of life (HRQOL) of initial benzodiazepine users was measured over time. Furthermore, benzodiazepine usage characteristics as determinants of change in mental and physical health status of the benzodiazepine users were examined.

METHODS

In the only pharmacy of a Dutch community of 13,500 and during four months from November 1994, all patients with a benzodiazepine prescription and no history of benzodiazepine use over a period of 12 months before inclusion, were invited to participate. A total of 106 initial benzodiazepine users were matched for age and gender. In a six-month follow-up study, HRQOL was measured with the RAND-36. Consequently, in a nested case control design, determinants of change in mental and physical functioning over the six-month period were analysed using the Mental Component Summary and the Physical Component Summary.

RESULTS

At baseline, initial benzodiazepine users showed a lower HRQOL as compared to reference subjects. After six-month follow-up, benzodiazepine users presented an absolute increase in HRQOL, while the reference subjects maintained a stable HRQOL. Diazepam and the male gender were associated with an increase in physical functioning over time. Younger age, a lower daily dose (DDD < 0.75) and a period of use between 16 and 60 days were associated with better mental functioning over time.

CONCLUSION

This study is one of the first to associate improvement in HRQOL over time of starting benzodiazepine users with specific usage characteristics, such as limited duration of use and a low dosage.

ADR related questions received by a telephone medicines information service and ADRs received by a spontaneous ADR reporting system: a comparison regarding patients and drugs

A telephone medicines information service (telephone service) has been available in the Netherlands since 1990. Patients can anonymously and free of charge ask a pharmacist all kinds of questions related to medication use. An analysis of the questions (n=7541) received by this service in 1994 showed that 28% of the questions predominantly related to adverse drug reactions (ADRs). A comparison was made between questions concerning ADRs received by the telephone service and suspected ADRs reported to the regionalized ADR reporting system LAREB regarding characteristics of the associated patients and medicines. In both systems approximately two out of three patients were women. LAREB received relatively more reports concerning patients of 60 years and older, whereas the telephone service received relatively more questions from patients aged 20-40 years. For most classes of medicines the observed proportion of encounters at both systems differed from the expected proportion estimated by the number of prescriptions in the same year. Antidepressants in particular were more frequently encountered at both systems than expected. There were clear differences between the telephone service and LAREB regarding the classes of medicines encountered. Reports of suspected ADRs submitted to LAREB more frequently involved antibiotics, antirheumatic products, anti-asthmatics, antihypertensives and topical antifungals, whereas questions concerning ADRs received by the telephone service significantly more frequently concerned drugs acting on the central nervous system (anxiolytics/hypnotics/sedatives, antidepressants and antipsychotic drugs) and corticosteroids. We are setting up further studies to investigate whether telephone services can serve as an additional tool in postmarketing surveillance for identifying potential drug safety issues.

Reduction in the therapeutic intensity of abortive migraine drug use during ACE inhibition therapy--a pilot study

INTRODUCTION

Since a few case reports have demonstrated some beneficial effects of angiotensin converting enzyme (ACE) inhibitors in migraine prevention, we were interested in studying the impact of ACE inhibitors and angiotensin II receptor antagonists (Ang II) on the consumption of specific abortive migraine drugs and, therefore, indirectly on the frequency of migraine attacks.

METHODS

Data from a large prescription database involving 95 patients initiating a specific abortive migraine drug (ergotamine or a triptan) and subsequently treated with either an ACE inhibitor or angiotensin receptor antagonist (index group: ACE/Ang II) or diuretic (reference group) were analysed. The effects of ACE/Ang II inhibition as well as diuretic therapy on reducing the frequency of migraine attacks were assessed by measuring the mean consumption of abortive migraine drug use, in DDDs per month ('therapeutic intensity'), before, during and after ACE/Ang II or diuretic therapy. A 'therapeutic fluctuation intensity estimate' of abortive migraine drug use for all patients was likewise calculated.

RESULTS

On an individual level, the therapeutic intensity (TI) fluctuation estimate, 'during' relative to 'before' ACE diuretic therapy, was significantly larger for the ACE/Ang II group (62% reduction) than for the diuretic group (24% reduction) (p = 0.02). For patients who continued abortive migraine drug use during and after ACE/Ang II or diuretic therapy, a significantly larger reduction in this estimate was observed during ACE/Ang II inhibition (68.9%) compared to during diuretic therapy (10.5% increase) (p = 0.004). The TI fluctuation estimate, after relative to 'during', had increased by 50.3% after ACE/Ang II inhibition and had reduced by 22.2% after diuretic treatment (p = 0.1).

CONCLUSIONS

A clear reduction in the TI of abortive migraine drug use during the use of ACE inhibitors as compared to diuretic treatment was observed. Our findings may indirectly support a positive effect of ACE/Ang II inhibition on the frequency and severity of migraine attacks, as observed in other studies and reports.

Incidence and determinants of antidepressant drug use in migraine patients

The purpose of this retrospective, follow-up study was to characterise the use of antidepressant medication in a defined migraine population and evaluate the determinants thereof. Data was obtained from the PHARMO-RLS prescription database. Our migraine population (2,517 people) included patients having commenced specific migraine drugs, ergotamine or sumatriptan, for the first time from January 1 1992 to December 31 1998. The corresponding date was termed the 'index date'. Non-migraine patients, those not having used any medication specific for migraine, were selected and equally matched (n=2,517). The cumulative incidence of initiating antidepressant treatment was estimated during two-year observation periods prior to and after the index date. Several demographic and comedication characteristics were assessed as potential determinants of antidepressant drug use within the migraine population. Other determinants included usage patterns ("therapeutic intensity") of ergotamine and sumatriptan, defined as the absolute number of Defined Daily Doses (DDDs) dispensed per patient during one year prior to initiation of antidepressant therapy. A total of 300 migraine patients (11.9%) and 213 non-migraine patients (8.5%) had initiated antidepressant treatment in the two-year period prior to or in the two-year period after the index date (RR adj 1.4; 95% CI 1.2-1.7). The cumulative incidence of initiation of antidepressant treatment for the migraine population was 3.0% per year prior to and 3.2% per year after the initiation of specific migraine analgesia. The concomitant use of benzodiazepines (RR adj 4.7; 95% CI 3.5-6.3), migraine prophylactic medication (RR adj 2.1; 95% CI 1.6-2.8) and heavy therapeutic intensity use of specific migraine analgesia, defined as >/=150 DDDs per year were highly predictive of antidepressant drug use within the migraine population. In conclusion, compared to the non-migraine population, the initiation of antidepressant treatment was only slightly higher in the migraine population. A number of determinants within the latter were found to be strongly associated with antidepressant drug use, the nature of which most likely reflects an increased severity of migraine whereby therapeutic needs are higher.

Migraine prophylactic medication usage patterns in The Netherlands

This study aims to investigate usage patterns of specific migraine prophylactic medications in ergotamine and triptan patients commencing this treatment for the first time during 1 January 1992 until 31 December 1998. Usage patterns of specific migraine prophylactic drugs were evaluated for each patient by accessing data from a large prescription database and were characterized as continued, switch or stop use during the patient observation period. Several patient and medication-related factors were explored in order to identify a possible relationship with the specific usage pattern defined. Approximately 75% of the study population (n = 729) had terminated (stop or switch) prophylactic treatment after 1 year. Age < 40 years (relative risk (RR) 1.9; 95% confidence interval (CI) 1.2-3.2) and the concomitant use of non-steroidal anti-inflammatory drugs (RR 3.2; 95% CI 1.2-5.5) or specific abortive migraine drugs resulted in a faster onset of treatment modification (switch). Overall, migraine prophylactic treatment is used for a relatively short period, probably attributable to the common limitations associated with migraine prophylaxis, such as poor compliance and/or limited therapeutic efficacy. Patterns of use can be influenced by a variety of factors, including age, type of prescriber and certain co-medication. Patient interview studies are required to clarify these issues further.

The impact of attitudes and beliefs on length of benzodiazepine use: a study among inexperienced and experienced benzodiazepine users

Prolonged benzodiazepine use is a widespread phenomenon in medical practice. In the present article, we argue that psychological models may contribute to our understanding of benzodiazepine use. This study examined variables derived from the theory of planned behaviour and the health belief model in relation to the length of benzodiazepine use. Data were collected from a sample of all benzodiazepine users with a request for this medicine in the only pharmacy in a Dutch community (N=467). Determinants of the length of benzodiazepine use were analysed separately for inexperienced and experienced users using structural equation modelling (SEM) analyses. For both groups, results showed that the intention to use benzodiazepines was a predictor of length of use. Attitudes towards benzodiazepine use had an indirect influence on length of use, through intentions. Furthermore, a positive attitude toward using benzodiazepines was related to the perceived norm of the prescriber. Experienced users were more inclined to consume benzodiazepines when they had less control over drug taking. In this group, the belief that benzodiazepine use leads to dependence was associated with less control over drug taking and a high intention to use the drug. In addition, older experienced users reported a higher intention to use the drug. For inexperienced users, the perceived attitude of the prescriber towards use of the medicine was a strong determinant. Finally, results of SEM-analyses showed that the model accounted for far more variance in behaviour for experienced users (67%), than for inexperienced users (18%).

Initial 3-month usage characteristics predict long-term use of benzodiazepines: an 8-year follow-up

OBJECTIVE

The aim of the study was to identify initial usage predictors for prolonged benzodiazepine use.

METHODS

An 8-year pharmacy data-based study (1983-1992) was carried out on a retrospective cohort of 425 initial benzodiazepine users. The setting was the only pharmacy in a community of 13,500 people.

RESULTS

Among the 425 initial users, 36% had a single initial exposure year, 50% had two to seven exposure years, and 14% had benzodiazepine use during all 8 years of follow-up. Prolonged use over more years was associated with an initial high number of prescriptions, elderly patients and initial use of hypnotics. Two patterns of irregular prolonged use were investigated: increase in use was associated with a shorter length of the first usage period and switching to another benodiazepine during the first 90 days; relapses of use were associated with a shorter length of first usage period and initial use of an anxiolytic. Gender and initial dosage were not associated with prolonged use at all.

CONCLUSION

During the first 90 days after initiation of benzodiazepine use, a number of determinants of prolonged benzodiazepine use were visible. The prescribers of these drugs and the pharmacists should advise rational use not only at the start but also at the moment of the first repeat prescription in order to prevent needless prolonged use and dependence.

Single use of sumatriptan: a patient interview study

OBJECTIVE

To investigate the possible reasons associated with the use of a single prescription of sumatriptan.

BACKGROUND

A few population-based studies concerning the usage patterns of sumatriptan have revealed a relatively high incidence (approximately 40%) of sumatriptan users who utilize only a single prescription of the drug.

DESIGN AND METHODS

Using automated prescription data from 11 community pharmacies, we identified single and multiple sumatriptan prescription recipients. The data were collected from May 1, 1998, to April 30, 2000. Several patient- and medication-related variables possibly associated with single recipiency of sumatriptan were analyzed. In addition, single recipients of sumatriptan were invited for an interview and asked a number of questions related to their clinical status and their experience with the medication.

RESULTS

Four hundred ninety-five, first-time users of sumatriptan were identified during the patient selection period, of whom 38% were single recipients of sumatriptan. Of the latter, 102 patients were considered eligible for interview. Reasons for terminating treatment after only 1 prescription included: inefficacy and/or occurrence of side effects, 78% (n=79); uncertain diagnosis of migraine, 39.2% (n=40); and reduction in headache frequency, 33.3% (n=34). Almost half of the population had terminated treatment without having consulted their physician. More than half relied upon the use of over-the-counter (OTC) analgesics after having tried sumatriptan. Compared to multiple users of sumatriptan, single recipients were far less likely to have used another form of migraine treatment prior to (odds ratio, 0.35; [95% confidence interval, 019 to 0.67]) and after (odds ratio, 0.34 [95% confidence interval, 0.19 to 0.63]) initiating sumatriptan. Furthermore, single recipients had demonstrated an increased tendency towards benzodiazepine use prior to receiving sumatriptan (odds ratio, 1.80 [95% confidence interval, 1.00 to 3.28]).

CONCLUSIONS

Single use of a sumatriptan prescription reveals some issues that may impact negatively the provision of effective migraine management. These include: rapidly developing dissatisfaction with the treatment provided and a lower tendency to seek out medical care. Our results also suggest that the drug may be used (inappropriately) as a diagnostic tool.

Comparing patterns of long-term benzodiazepine use between a Dutch and a Swedish community

BACKGROUND

There is much concern about the widespread long-term use of benzodiazepines. Utilisation data can give a foundation for interventions for appropriate use.

OBJECTIVE

To compare long-term usage patterns of benzodiazepines in a Dutch and a Swedish community in different periods.

METHODS

Eight-year follow-up patterns of use were investigated with respect to the characteristics of those who continued use over the whole follow-up period. In the Dutch community of 13,500, the data of a cohort of 1358 benzodiazepine users were analysed during the years 1984-1991; in the Swedish community of 20,000 people, a cohort of 2038 benzodiazepine users was followed from 1976.

RESULTS

At the end of the follow-up period, 32.9% of the Dutch cohort and 33% of the Swedish cohort had continued use of benzodiazepines. The two overall survival curves showed similar patterns. Stratification for age, gender, previous versus initial use and heavy versus non-heavy use showed comparable proportions of patients continuing benzodiazepine use over time.

CONCLUSION

The parallels in the results of two cohorts in different countries and different periods are striking and give support to the idea to stimulate interventions to reduce long-term benzodiazepine use.

Changes in prescribed drug doses after market introduction

PURPOSE

The establishment of recommended dosing regimens has always been a difficult aspect of drug development. This paper examines the extent to which postmarketing prescribing deviates from initially recommended dosing regimens. We used the World Health Organization's (WHO) periodically updated compilation of the 'Defined Daily Dose' (DDD) to reflect prevailing patterns of prescribing in national markets. The aim of this study was to evaluate DDD changes over time (1982-2000) and to identify possible determinants of these changes.

METHODS

Data on DDD changes were obtained from the WHO's Oslo Collaborating Centre. We performed a case-control analysis in which we compared drugs with (cases) and without (controls) postmarketing changes in DDD on possible determinants associated with DDD change.

RESULTS

We found 115 instances of a change of DDD in the period 1982-2000 (45 (39.1%) increases and 70 (60.9%) decreases). Antibiotics showed the greatest number of changes in DDD: predominantly increases in the 1980s, while the 1990s were dominated by decreases in DDD of mostly cardiovascular drugs.

CONCLUSION

Changes in DDD reflect the outcome of a melange of forces, including misconceptions of dose requirements during pre-market development of drug and postmarketing changes in pharmacotherapeutic knowledge, clinical concepts, economic forces, and, in the case of anti-infective agents, changing patterns of resistance/sensitivity of target microorganisms to the anti-infective agent(s) in question.

Incidence and determinants of migraine prophylactic medication in the Netherlands

OBJECTIVE

To estimate and examine the incidence and determinants of initiation of migraine-prophylactic therapy as well as the corresponding drug of choice over a period of 5 years following the use of specific abortive migraine drugs.

METHODS

By accessing data from a large prescription database, an identification of patients treated with ergotamine or a triptan from 1 January 1994 to 31 December 1998 was made. The cumulative incidence of initiation of migraine-prophylactic drugs (beta-blockers, serotonin antagonists, specific calcium antagonists, amitriptyline, clonidine and valproic acid) was estimated in patients following the use of ergotamine or a triptan. An assessment of the migraine-prophylactic drug of first choice was also performed. A few baseline determinants were analysed to highlight a possible association with the initiation of prophylactic therapy: age, gender, type of abortive migraine drug use and year of prophylaxis. Additional determinants included the analysis of drug-utilisation patterns, such as the consumption and switch patterns of abortive migraine drug use as well as co-medication use prior to prophylaxis. For this particular analysis a reference group (patients not having commenced prophylaxis) was selected from the initial study population.

RESULTS

After having satisfied eligibility criteria, a total of 3999 first-time users of ergotamine and triptans were included of whom 479 (12%) had initiated migraine-prophylactic therapy. This corresponded to an incidence density of 6.0 per 100 person-years and was highest for patients younger than 45 years and for multiple abortive migraine drug users. The incidence fell considerably from 12.0 person-years in 1994 to 5.1 person-years in 1998. More than half of the patients had been prescribed a beta-blocker as the migraine-prophylactic drug of first choice by both general practitioners and neurologists. The use of antidepressants and/or benzodiazepines and oral contraceptives was significantly higher in patients starting prophylaxis compared with those who did not. The consumption of abortive migraine drug use (4.0 defined daily doses per month vs 3.7 defined daily doses per month), and switch patterns (27.1% vs 30.9%) were similar for patients starting and not starting prophylaxis.

CONCLUSION

The overall incidence of initiation of migraine-prophylactic therapy following the use of abortive migraine analgesics was 6.0% per year and fell considerably during 5 years of the study. Beta-blockers were the migraine-prophylactic drugs of first choice for general practitioners and neurologists. In our study we could not determine any factors clearly associated with the initiation of migraine prophylaxis besides prior use of antidepressants and benzodiazepines. A future assessment of the usage patterns of migraine-prophylactic drugs may provide detailed information concerning the effectiveness and tolerability.

The Dutch cohort of sildenafil users: baseline characteristics

OBJECTIVE

To identify a Dutch cohort of sildenafil users and describe their baseline characteristics.

PATIENTS AND METHODS

Each pharmacy in The Netherlands (n = 1571) was asked to identify prospectively the first 20 sildenafil prescriptions in their pharmacy over 1 year, and to complete and return a registration form. The collected data included patient characteristics, the details of the sildenafil prescription (date, prescriber, number of prescriptions, dosing), and the use of co-medication by the patient in the year preceding the sildenafil prescription.

RESULTS

Data were collected from 4460 sildenafil prescriptions during the year under study, relating to 3477 individual patients. Most of the cohort had cardiovascular morbidity or diabetes. Sildenafil seems to have been used by a new, previously untreated population of patients with erectile dysfunction. In addition, 69 men were identified who could have been using nitrates and sildenafil concomitantly.

CONCLUSION

A cohort of patients using sildenafil was identified and characterized; they appeared to be representative of sildenafil users in The Netherlands. This cohort will be followed prospectively to evaluate the medical status (particularly cardiovascular) of the patients with time.

Psychotropic drug use in intellectually disabled group-home residents with behavioural problems

Little is known about psychiatric and behavioural factors associated with psychotropic drug use and how appropriately these drugs are prescribed in settings for people with intellectual disabilities. The aim of this study was to measure the point prevalence of psychotropic drug use in a problem-behaviour group (PBG) consisting of intellectually disabled residents of group homes compared to a random group (RG), and to gain insight in possible factors that are associated with group membership. From all group homes in the Netherlands, 573 problematic residents were selected by the staff (one resident from each home) and 1479 residents were randomly sampled from all of the homes. Mental health problems were measured using the Reiss Screen for Maladaptive Behaviour and the Psychopathology Instrument for Mentally Retarded Adults. The response rate in the PBG was 68.9 % and in the RG 71.7 %. Psychotropics (excluding anticonvulsants) were used by 52.6 % of the PBG and by 22.8 % of the RG. Young age, psychotic, anxiety, and aggression symptoms were significantly associated with the PBG, as was the use of antipsychotics and antidepressants. The PBG more often used multiple (three or more) drugs (17.3 %) than the RG (7.3 %). A low prevalence of antidepressants or mood stabilisers, antipsychotics, and anxiolytics was found in residents with affective, psychotic, or anxiety symptoms. We conclude that psychotropic drug use in the PBG compared to the RG was high. It is likely that the group-home staff finds it difficult to deal with young people with socially disruptive behaviour, which is underlined by our finding of high prevalence of antipsychotics and multiple-drug therapy in the PBG. Finally, our findings suggest that a considerable number of residents with psychiatric or behavioural symptoms are undertreated.

Epidemiology of fractures in England and Wales

Records from the General Practice Research Database were used to derive age- and gender-specific fracture incidence rates for England and Wales during the period 1988-1998. In total, 103,052 men and 119,317 women in the sample of 5 million adults sustained a fracture over 10.4 million and 11.2 million person-years (py) of follow-up. Among women, the most frequent fracture sites were the radius/ulna (30.2 cases per 10,000 py) and femur/hip (17.0 per 10,000 py). In men, the most common fracture was that of the carpal bones (26.2 per 10,000 py); the incidence of femur/hip fracture was 5.3 per 10,000 py. Varying patterns of fracture incidence were observed with increasing age; whereas some fractures became more common in later life (vertebral, distal forearm, hip, proximal humerus, rib, clavicle, pelvis), others were more frequent in childhood and young adulthood (tibia, fibula, carpus, foot, ankle). The lifetime risk of any fracture was 53.2% at age 50 years among women, and 20.7% at the same age among men. Whereas fractures of the proximal femur and vertebral body were associated with excess mortality over a 5 year period following fracture diagnosis among both men and women, fractures of the distal forearm were associated with only slight excess mortality in men. This study provides robust estimates of fracture incidence that will assist health-care planning and delivery.

Spontaneous lapses in dosing during chronic treatment with selective serotonin reuptake inhibitors

BACKGROUND

In previous research, lapses in dosing of paroxetine or sertraline were associated with significantly more discontinuation symptoms and deterioration of depressive symptomatology compared with fluoxetine.

AIMS

To evaluate dosing lapses in patients chronically treated with selective serotonin reuptake inhibitors (SSRIs) in uncontrolled circumstances.

METHOD

In a prospective observational study we evaluated compliance data in chronic users of SSRIs using electronic drug exposure monitors.

RESULTS

During a 3-month follow-up we found that 50/69 (72.5%) patients missed at least one dosing day and 20/69 (29.0%) missed two or more consecutive days.

CONCLUSIONS

About 30% of patients treated with short-acting SSRIs had dosing lapses of 2 or more days, which, as described in prior studies, is long enough to result in clinically relevant deterioration of mental status.

Pyrazinamide use as a method of estimating under-reporting of tuberculosis

OBJECTIVE

To develop a method of validating the notification of active tuberculosis by physicians in the Netherlands.

METHOD

The chemotherapeutic agent pyrazinamide was used as a marker for the occurrence of tuberculosis. On the basis of defined daily doses (DDD) of pyrazinamide dispensed to out-patients, an estimate was made of the number of patients with tuberculosis in the Netherlands in the period 1994-1998. DDD is a technical unit of measurement and does not necessarily reflect the recommended or actual dose used. Usually it is based on the average dosage per day for the main indication in adults with normal organ function. The Dutch Drug Information Project (GIP) of the Health Care Insurance Board (CVZ) provided the DDD data. Based on the notification of tuberculosis patients to the Netherlands Tuberculosis Register (NTR) we calculated how much pyrazinamide (measured in DDDs) these patients would have used depending on their body weight.

RESULTS

The number of DDDs prescribed according to the GIP pharmacy records differed by only 8% from the number of DDDs calculated on the basis of notification to the NTR; 6889 patients should have been registered instead of 6349.

CONCLUSION

The close correlation between the use of pyrazinamide as measured by the GIP and NTR provides strong evidence that in the Netherlands tuberculosis is reported in conformity with the guidelines for notifiable diseases. The method was simple to apply and may deserve follow-up in other countries.

Risk of extrapyramidal syndromes with haloperidol, risperidone, or olanzapine

OBJECTIVE

To compare the risk of extrapyramidal syndrome (EPS) between risperidone, olanzapine, and haloperidol, taking into account patients' past antipsychotic drug use and past EPS.

METHODS

Data were obtained from the PHARMO-database, containing filled prescriptions of 450,000 community-dwelling people in the Netherlands from 1986 through 1999. We defined cohorts of first-time users of haloperidol, risperidone, or olanzapine aged 15 to 54 years. In the first 90 days of treatment, we assessed the occurrence of EPS, defined as first use of any antiparkinsonian agent. We estimated relative risks of EPS for risperidone and olanzapine versus haloperidol using a Cox proportional hazards model. Patients were subdivided according to prior use of antipsychotic and antiparkinsonian drugs.

RESULTS

We identified 424 patients starting treatment with haloperidol, 243 with risperidone, and 181 with olanzapine. Prior use of antipsychotic plus antiparkinsonian medication was significantly more frequent among users of risperidone and olanzapine than in those using haloperidol (36.2%, 40.3%, and 4.5%, respectively; p < 0.001). Within most subgroups of comparable treatment history, patients using risperidone and olanzapine showed reduced risks of EPS compared with haloperidol, although some of these findings did not reach statistical significance (RR 0.03-0.22). However, this was not observed for patients using risperidone who had experienced EPS in the past (RR 1.30; 95% CI 0.24 to 7.18).

CONCLUSIONS

In general, we observed reduced risks of EPS for risperidone and olanzapine compared with haloperidol within subgroups of patients with a similar treatment history. However, the added value of risperidone in patients who have experienced EPS in the past needs further study.

Determinants of multiple psychotropic drug use in patients with mild intellectual disabilities or borderline intellectual functioning and psychiatric or behavioral disorders

Prevalence rates of psychotropic drug use in people with intellectual disabilities are high and pharmacotherapy is often attempted with multiple drugs. The presence of disruptive behavior is an important factor associated with the use of psychotropic drugs in this population. We wanted to gain insight into prevalence and determinants of multiple psychotropic drug use among patients with mild intellectual disabilities or borderline intellectual functioning with psychiatric or behavioral disorders. Therefore, data on psychotropics and possible determinants of use were retrospectively collected during 1992-1997 in a specialized closed ward of a Dutch general psychiatric hospital. We defined multiple drug use as concomitant prescription (regular or as needed) of a combination of benzodiazepines/tranquilizers/antipsychotics/anticonvulsants/anti-depressants. Multiple drug use, seen in 48% of the patients, was associated with a long duration of stay, psychosis, aggressive, bizarre, attention-seeking behavior and involuntary measures. We conclude that it is likely that difficulties in the management of socially disruptive behavior are often countered by multiple drug prescription.

Determinants of signal selection in a spontaneous reporting system for adverse drug reactions

AIMS

Detection of new adverse drug reactions (ADR) after marketing is often based on a manual review of reports sent to a Spontaneous Reporting System (SRS). Among the many potential signals that are identified, only a limited number are important enough to require further attention. The goal of this study is to gain insight into factors contributing to the selection and dissemination of possible signals originating from the SRS maintained by the Netherlands Pharmacovigilance Foundation.

METHODS

In a case control design, all signals (n = 42) disseminated to the Medicines Evaluation Board from the second quarter of 1997 until the third quarter of 2000, which could be expressed as a combination of a single ATC code and a single WHO preferred term, were included. For each case, four controls were matched in time. Logistic regression analysis was used to investigate the influence of various factors, such as the fact whether the ADR or drug is new, the strength of the association, the seriousness of the reaction and the documentation of the reports.

RESULTS

Multivariate analysis showed that the presence of a 'serious report' (Odds Ratio 3.8, 95% CI 1.3, 11.0), a WHO 'critical term' (OR 4.7, 95% CI 1.8, 13), the ADR being unlabelled (OR 6.1, 95% CI 2.3, 16) and the presence of a disproportionate association (OR 3.5, 95% CI 1.4, 8) were all independently associated with signal selection. The number of reports and the time after marketing of the drug had no influence.

CONCLUSIONS

This study showed that selection of signals is based on both qualitative and quantitative aspects. Knowledge of these factors may improve the efficiency of the underlying signal selection process.