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1.  Risk of Fracture with Thiazolidinediones: An Individual Patient Data Meta-Analysis 
Background: The use of thiazolidinediones (TZDs) has been associated with increased fracture risks. Our aim was to estimate the risk of fracture with TZDs in three different healthcare registries, using exactly the same study design, and to perform an individual patient data meta-analysis of these three studies.
Methods: Population-based cohort studies were performed utilizing the British General Practice Research Database (GPRD), the Dutch PHARMO Record Linkage System (RLS), and the Danish National Health Registers. In all three databases, the exposed cohort consisted of all patients (aged 18+) with at least one prescription of antidiabetic (AD) medication. Cox proportional hazards models were used to estimate hazard ratios (HRs) of fracture. The total period of follow-up for each patient was divided into periods of current exposure and past exposure, with patients moving between current and past use.
Results: In all three registries, the risk of fracture was increased for women who were exposed to TZDs: HR 1.48 (1.37–1.60) in GPRD, HR 1.35 (1.15–1.58) in PHARMO, and HR 1.22 (1.03–1.44) in Denmark. Combining the data in an individual patient data meta-analysis resulted, for women, in a 1.4-fold increased risk of any fracture for current TZD users versus other AD drug users [adj. HR 1.44 (1.35–1.53)]. For men, there was no increased fracture risk [adj. HR 1.05 (0.96–1.14)]. Risks were increased for fractures of the radius/ulna, humerus, tibia/fibula, ankle, and foot, but not for hip/femur or vertebral fractures. Current TZD users with more than 25 TZD prescriptions ever before had a 1.6-fold increased risk of fracture compared with other AD drug users [HR 1.59 (1.46–1.74)].
Conclusion: In this study, we consistently found a 1.2- to 1.5-fold increased risk of fractures for women using TZDs, but not for men, across three different healthcare registries. TZD users had an increased risk for fractures of the extremities, and risks further increased for prolonged users of TZDs.
doi:10.3389/fendo.2013.00011
PMCID: PMC3582108
thiazolidinediones; fracture; individual patient data; meta-analysis; epidemiology
2.  The role of Periodic Safety Update Reports in the safety management of biopharmaceuticals 
Purpose
To describe and assess the outcomes of Periodic Safety Update Report (PSUR) evaluations of biopharmaceuticals.
Methods
A cross-sectional analysis was performed of follow-up requirements of PSURs submitted for centrally approved biopharmaceuticals in the European Union between 1 July 2008 and 30 June 2010. A follow-up analysis on a subset of products that submitted multiple PSURs within the study period was also performed.
Results
The cross-sectional analysis included 70 PSURs. Potential safety concerns occurred in 57 (83 %) of all PSURs, and 26 (37 %) concluded a need to change the Summary of Product Characteristics (SPC). In comparison to newer products, products authorized for more than 10 years contained significantly fewer potential safety concerns (60 vs. 92 %; p < 0.01) and required fewer SPC changes (15 vs. 46 %; p = 0.03). For 45 products, multiple PSURs were submitted that could be included in a follow-up analysis. For this subset of products, of the 106 newly identified safety potential safety issues, 7 (7%) resulted in requirements for label changes in the following PSUR.
Conclusions
PSURs facilitate communication between regulators and marketing authorization holders. Potential safety concerns occur for the majority of biopharmaceuticals and throughout their lifecycle, but for established products PSUR evaluations rarely lead to regulatory actions.
doi:10.1007/s00228-012-1317-3
PMCID: PMC3548093  PMID: 22706615
Periodic Safety Update Report; Pharmacovigilance; Biopharmaceuticals; Safety
3.  Risk of Fracture with Thiazolidinediones: Disease or Drugs? 
Calcified Tissue International  2012;90(6):450-457.
The use of thiazolidinediones (TZDs) has been associated with an increased fracture risk. In addition, type 2 diabetes mellitus (T2DM) has been linked with fracture. We evaluated to what extent the association between TZD use and fracture risk is related to the drug or to the underlying disease. We conducted a population-based cohort study using the Danish National Health Registers (1996–2007), which link pharmacy data to the national hospital registry. Oral antidiabetic users (n = 180,049) were matched 1:3 by year of birth and sex to nonusers. Cox proportional hazards models were used to estimate hazard ratios (HRs) of fracture. Time-dependent adjustments were made for age, comorbidity, and drug use. We created a proxy indicator for the severity of disease. The first stage was defined as current use of either a biguanide or a sulfonyluerum, the second stage as current use of a biguanide and a sulfonyluerum at the same time, the third stage as patients using TZDs, and the fourth stage as patients using insulin. The risk of osteoporotic fracture was increased 1.3-fold for stages 3 and 4 compared with controls. Risk with current TZD use (stage 3 HR = 1.27, 95 % CI 1.06–1.52) and risk with current use of insulin (stage 4 HR = 1.25, 95 % CI 1.20–1.31) were similar. In the first (HR = 1.15, 95 % CI 1.13–1.18) and second (HR = 1.00, 95 % CI 0.96–1.04) stages risks were lower. Risk of osteoporotic fracture was similar for TZD users and insulin users. When studying fracture risk with TZDs, the underlying T2DM should be taken into account.
doi:10.1007/s00223-012-9591-8
PMCID: PMC3349019  PMID: 22488176
Thiazolidinedione; Type 2 diabetes mellitus; Fracture risk; Osteoporosis
4.  Risk of Death and Cardiovascular Outcomes with Thiazolidinediones: A Study with the General Practice Research Database and Secondary Care Data 
PLoS ONE  2011;6(12):e28157.
Objective
To describe the likely extent of confounding in evaluating the risks of cardiovascular (CV) events and mortality in patients using diabetes medication.
Methods
The General Practice Research Database was used to identify inception cohorts of insulin and different oral antidiabetics. An analysis of bias and incidence of mortality, acute coronary syndrome, stroke and heart failure were analysed in GPRD, Hospital Episode Statistics and death certificates.
Results
206,940 patients were identified. The bias analysis showed that past thiazolidinedione users had a lower mortality risk compared to past metformin users. There were no differences between past users of rosiglitazone and pioglitazone (adjusted RR of 1.04; 95% CI 0.93–1.18). Current rosiglitazone users had an increased risk of death (adjusted RR 1.20; 95% CI 1.08–1.34) and of hospitalisation for heart failure (adjusted RR of 1.73; 95% CI 1.19–2.51) compared to current pioglitazone users. Risk of mortality was increased two-fold shortly after starting rosiglitazone. Excess risk of death over 3 years with rosiglitazone was 0.3 per 100 in those aged 50–64 years, 2.0 aged 65–74, 3.0 aged 75–84, and 7.0 aged 85+. The cause of death with rosiglitazone was more likely to be due to a disease of the circulatory system.
Conclusions
Higher risks for death (overall and due to cardiovascular disease) and heart failure were found for rosiglitazone compared to pioglitazone. These excess risks were largest in patients aged 65 years or older. The European regulatory decision to suspend rosiglitazone is supported by this study.
doi:10.1371/journal.pone.0028157
PMCID: PMC3229530  PMID: 22164237
5.  Is aspirin useful in patients on lithium? A pharmacoepidemiological study related to bipolar disorder 
Objectives
Administration to rats of mood stabilizers approved for bipolar disorder (BD) downregulates markers of the brain arachidonic acid (AA, 20:4n-6) metabolic cascade, including phospholipase A2 (PLA2) and cyclooxygenase (COX) expression. We hypothesized that other agents that target the brain AA cascade, nonsteroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids, also would ameliorate BD symptoms.
Methods
Medication histories on subjects who had been prescribed lithium were collected from the Netherlands PHARMO Record Linkage System. Data were stratified according to drug classes that inhibit PLA2 and/or COX enzymes, and duration of use. Incidence density (ID) of medication events (dose increase or substance change) was used as a proxy for clinical worsening. ID ratios in patients with the inhibitors plus lithium were compared to ratios in patients using lithium alone.
Results
Low-dose acetylsalicylic acid (aspirin) significantly reduced the ID ratio of medication events, independent of use duration. The ID ratios of NSAIDs and glucocorticoids did not differ significantly from 1.0 if prescribed for ≥ 180 or ≥ 90 days, but exceeded 1.0 with shorter use. Selective COX-2 inhibitors had no significant effect and multiagent administration increased the ID ratio above 1.0.
Conclusions
Low-dose aspirin produced a statistically significant duration-independent reduction in the relative risk of clinical deterioration in subjects on lithium, whereas other NSAIDs and glucocorticoids did not. These tentative findings could be tested on larger databases containing detailed information about diagnosis and disease course, as well as by controlled clinical trials. (238 words)
doi:10.1016/j.plefa.2009.10.007
PMCID: PMC2818404  PMID: 19939659
bipolar disorder; aspirin; NSAIDs; glucocorticoids; lithium; arachidonic acid; pharmacoepidemiology
6.  Functional foods: the case for closer evaluation 
BMJ : British Medical Journal  2007;334(7602):1037-1039.
Current regulations focus on the mandatory safety evaluation of functional foods before they come to market, but Nynke de Jongand colleagues argue that the effects of such foods should also be evaluated after they have been launched
doi:10.1136/bmj.39196.666377.BE
PMCID: PMC1871804  PMID: 17510152
7.  Superior efficacy of new medicines? 
Purpose
To provide an overview of and discuss newly authorised medicines with an improved efficacy.
Methods
This analysis focussed on new medicines with an improved efficacy based on the results of randomised active control trials. Information on comparative efficacy was obtained from the European Medicines Agency European Public Assessment Reports.
Results
Between 1999 and 2005 we identified 122 new medicines with a new active substance. Of these, 13 (10%) were shown to be superior to already available medicines in terms a statistically significant difference in primary clinical endpoints.
Conclusions
A proven advantage in efficacy at an early stage of drug development is the exception rather than the rule. The absence of evidence demonstrating differences between medicines does not necessarily mean that there are no actual differences. Optimal pharmacotherapy would benefit from more comparative research in the development of new medicines. The results of comparative trials need to be critically evaluated for their specific value in clinical practice. To this end, prescription data may be helpful.
doi:10.1007/s00228-010-0808-3
PMCID: PMC2853699  PMID: 20224944
Added therapeutic value; Comparative information; Market authorisation; Randomised active control trials; Superiority trials
9.  Predictors of orphan drug approval in the European Union 
Objective
To encourage the development of drugs for rare diseases, orphan drug legislation has been introduced in the USA (1983) and in the EU (2000). Recent literature discusses factors that may influence the development of new orphan medicinal products in the EU. This study aims to identify predictors for successful marketing authorisation of potential orphan drugs in the EU.
Methods
A comparison between randomly selected authorised and a matched sample of not-yet-authorised orphan drug designations has been performed. Determinants in the study included characteristics of the indication, of the product and of the sponsor. Data were collected from the public domain only.
Results
Orphan drug approval was strongly associated with previous experience of the sponsor in obtaining approval for another orphan drug (OR = 17.3, 95% CI = 5.6–53.1). Furthermore, existing synthetic entities compared to biotechnology products tended to have a higher likelihood of reaching approval status (OR = 3.9, 95% CI = 0.9–16.6).
Conclusion
This study showed that experience of a company in developing orphan drugs is an important predictor for subsequent authorisation of other orphan drugs. The same applies for existing (synthetic) molecules, for which much knowledge is available. Further research should be directed towards studying the quality of the clinical development program of those designated orphan medicinal products not reaching approval status.
doi:10.1007/s00228-007-0454-6
PMCID: PMC2668549  PMID: 18210097
Orphan drugs; Rare diseases; Drug development; Regulatory affairs
10.  A simple score for estimating the long-term risk of fracture in patients with multiple sclerosis 
Neurology  2012;79(9):922-928.
Objective:
To derive a simple score for estimating the long-term risk of osteoporotic and hip fracture in individual patients with MS.
Methods:
Using the UK General Practice Research Database linked to the National Hospital Registry (1997–2008), we identified patients with incident MS (n = 5,494). They were matched 1:6 by year of birth, sex, and practice with patients without MS (control subjects). Cox proportional hazards models were used to calculate the long-term risk of osteoporotic and hip fracture. We fitted the regression model with general and specific risk factors, and the final Cox model was converted into integer risk scores.
Results:
In comparison with the FRAX calculator, our risk score contains several new risk factors that have been linked with fracture, which include MS, use of antidepressants, use of anticonvulsants, history of falling, and history of fatigue. We estimated the 5- and 10-year risks of osteoporotic and hip fracture in relation to the risk score. The C-statistic was moderate (0.67) for the prediction of osteoporotic fracture and excellent (0.89) for the prediction of hip fracture.
Conclusion:
This is the first clinical risk score for fracture risk estimation involving MS as a risk factor.
doi:10.1212/WNL.0b013e318266faae
PMCID: PMC3425841  PMID: 22895583

Results 1-10 (10)