Aukje K. Mantel-Teeuwisse

Safety-Related Regulatory Actions for Biologicals Approved in the United States and the European Union

CONTEXT Biologicals are a relatively new class of medicines that carry specific risks (eg, immunogenicity). However, limited information is available on the nature and timing of safety problems with their use that were identified after approval. OBJECTIVE To determine the nature, frequency, and timing of safety-related regulatory actions for biologicals following approval in the United States and/or the European Union. DESIGN AND SETTING Follow-up of a group of biologicals approved in the United States and/or European Union between January 1995 and June 2007. Vaccines, allergenic products, and products for further manufacture and transfusion purposes were excluded. MAIN OUTCOME MEASURES Nature, frequency, and timing of safety-related regulatory actions defined as (1) dear healthcare professional letters (United States) and direct healthcare professional communications (European Union), (2) black box warnings (United States), and (3) safety-related marketing withdrawals (United States and European Union) issued between January 1995 and June 2008. RESULTS A total of 174 biologicals were approved (136 in the United States and 105 in the European Union, of which 67 were approved in both regions). Eighty-two safety-related regulatory actions (46 dear healthcare professional letters, 17 direct healthcare professional communications, 19 black box warnings, and no withdrawals) were issued for 41 of the 174 different biologicals (23.6%). The probability of a first safety-related regulatory action, derived from Kaplan-Meier analyses, was 14% (95% confidence interval [CI], 9%-19%) 3 years after approval and 29% (95% CI, 20%-37%) 10 years after approval. Biologicals first in class to obtain approval had a higher risk for a first safety-related regulatory action compared with later approved products in that class (12.0/1000 vs 2.9/1000 months, respectively; hazard ratio, 3.7 [95% CI, 1.5-9.5]). Warnings mostly concerned the classes general disorders and administration site conditions, infections and infestations, immune system disorders and neoplasms benign, malignant, and unspecified. CONCLUSIONS The nature of safety problems identified after approval for biologicals is often related to the immunomodulatory effect (infections). Because the biologicals first to be approved in a class were more likely to be subjected to regulatory action, close monitoring is recommended.

Differences in the availability of medicines for chronic and acute conditions in the public and private sectors of developing countries

OBJECTIVE To investigate potential differences in the availability of medicines for chronic and acute conditions in low- and middle-income countries. METHODS Data on the availability of 30 commonly-surveyed medicines - 15 for acute and 15 for chronic conditions - were obtained from facility-based surveys conducted in 40 developing countries. Results were aggregated by World Bank country income group and World Health Organization region. FINDINGS The availability of medicines for both acute and chronic conditions was suboptimal across countries, particularly in the public sector. Generic medicines for chronic conditions were significantly less available than generic medicines for acute conditions in both the public sector (36.0% availability versus 53.5%; P = 0.001) and the private sector (54.7% versus 66.2%; P = 0.007). Antiasthmatics, antiepileptics and antidepressants, followed by antihypertensives, were the drivers of the observed differences. An inverse association was found between country income level and the availability gap between groups of medicines, particularly in the public sector. In low- and lower-middle income countries, drugs for acute conditions were 33.9% and 12.9% more available, respectively, in the public sector than medicines for chronic conditions. Differences in availability were smaller in the private sector than in the public sector in all country income groups. CONCLUSION Current disease patterns do not explain the significant gaps observed in the availability of medicines for chronic and acute conditions. Measures are needed to better respond to the epidemiological transition towards chronic conditions in developing countries alongside current efforts to scale up treatment for communicable diseases.

Drug-Induced lipid changes: a review of the unintended effects of some commonly used drugs on serum lipid levels.

Many drugs besides lipid-lowering drugs affect serum lipid levels in either a potentially harmful or beneficial way, and may therefore increase or decrease the risk of cardiovascular disease.Diuretics, β-blocking agents, progestogens, combined oral contraceptives containing ‘second generation’ progestogens, danazol, immunosuppressive agents, protease inhibitors and enzyme-inducing anticonvulsants adversely affect the lipid profile. They increase total cholesterol, low density lipoprotein cholesterol and triglycerides by up to 40, 50 and 300%, respectively, and decrease high density lipoprotein cholesterol by a maximum of 50%. Conversely, α-blocking agents, estrogens, hormone replacement therapy, combined oral contraceptives containing ‘third generation’ progestogens, selective estrogen receptor modulators, growth hormone and valproic acid show mostly beneficial effects on the lipd profile. Some drugs, for example, isotretinoin, acitretin and antipsychotics, mainly elevate triglyceride levels.Adverse or beneficial effects on serum cholesterol levels do not always translate into a higher or lower, respectively, incidence of cardiovascular disease, because these drugs may influence cardiovascular risk through multiple pathways. In some cases, excessive cholesterol levels occur, for example, with protease inhibitor therapy, and several cases of pancreatitis attributable to drug-induced hypertriglyceridaemia have been reported.Some general guidelines on the management of drug-induced dyslipidaemia can be given. Replacement of the dyslipidaemia-inducing drug by an equivalent alternative therapy is preferred. However, such alternatives are often difficult to find. If there is no equivalent alternative and treatment with the dyslipidaemia-inducing drug must be initiated, monitoring of serum lipid levels is important. If drug use is expected to be long term, the existing guidelines for the management of dyslipidaemia in the general population can be applied to drug-induced dyslipidaemia. In cases of extreme hyperlipidaemia, medication use should be reassessed.

HMG-CoA reductase inhibitors, other lipid-lowering medication, antiplatelet therapy, and the risk of venous thrombosis

Summary.  Background: Statins [3‐hydroxymethyl‐3‐methylglutaryl coenzyme A (HMG‐CoA) reductase inhibitors] and antiplatelet therapy reduce the risk of atherosclerotic disease. Besides a reduction of lipid levels, statins might also have antithrombotic and anti‐inflammatory properties, and anti‐platelet therapy reduces clot formation. We have studied the risk of venous thrombosis with use of statins, other lipid‐lowering medication, and antiplatelet therapy. Materials and methods: Patients with a first episode of deep vein thrombosis in the leg or pulmonary embolism between March 1999 and September 2004 were included in a large population‐based case–control study (MEGA study). Control subjects were partners of patients (53%) or recruited via a random‐digit‐dialing method (47%). Participants reported different all‐medication use in a questionnaire. Results: Of 4538 patients, 154 used statins (3.3%), as did 354 of 5914 control subjects (5.7%). The use of statins [odds ratio (OR) 0.45; 95% confidence interval (CI) 0.36–0.56] but not other lipid‐lowering medications (OR 1.22; 95% CI 0.62–2.43), was associated with a reduced venous thrombosis risk as compared with individuals who did not use any lipid‐lowering medication, after adjustment for age, sex, body mass index, atherosclerotic disease, antiplatelet therapy and use of vitamin K antagonists. Different types and various durations of statin therapy were all associated with a decreased venous thrombosis risk. Antiplatelet therapy also reduced venous thrombosis risk (OR 0.56; 95% CI 0.42–0.74). However, sensitivity analyses suggested that this effect is most likely explained by a so‐called ‘healthy user effect’. Simultaneous use of medication most strongly reduced venous thrombosis risk. Conclusion: These results suggest that the use of various types of statins is associated with a reduced risk of venous thrombosis, whereas antiplatelet therapy and other lipid‐lowering medications are not.

Differences in external price referencing in Europe—A descriptive overview

OBJECTIVE This study aimed to provide an up-to-date description as well as comparative analysis of the national characteristics of pharmaceutical external price referencing (EPR) in Europe. METHODS Review of the country-specific PPRI (Pharmaceutical Pricing and Reimbursement Information) Pharma Profiles written by representatives of the PPRI Network. The Profiles were analysed according to predefined criteria. RESULTS Of 28 analysed European countries 24 applied EPR in 2010. The majority of countries have statutory rules to implement EPR. Most countries had less than 10 countries in their reference baskets. Higher income countries tend to include higher income countries in their basket, whereas lower income countries refer to lower income countries. Taking the average price of all countries in the basket as the basis to calculate the national price was the most common strategy (n=8). The methodology of EPR has changed in most European countries over the past 10 years (n=19). CONCLUSIONS EPR is a widely used pricing policy in Europe and is still actively used as well as adjusted by national authorities. However, we still see room for improvement by implementing more detailed legislations in terms of the revision of prices and by identifying alternative countries in case a product is not on the market. We also see the need for formal information sharing (e.g. congresses dedicated to pricing strategies and systems) with other public pricing authorities to learn about the different EPR methodologies as well as the national experiences. These congresses might also give room to better understand national pricing methods including discussions on possible limitations of these pricing methods.

Comparison of different methods to estimate prevalence of drug use by using pharmacy records

Several methods to estimate prevalence of drug use are available, which may complicate a valid comparison of these estimates. Standardization may contribute to more valid comparisons. We compared different methods to estimate prevalence of drug use by using pharmacy records. Data were obtained from the Dutch population-based PHARMO-database comprising medication histories of 300,000 subjects. Five point prevalences and a 1-year prevalence of cholesterol-lowering drug use were estimated in 1995. Four point prevalences differed in data handling before estimating prevalence (e.g., correction for irregular drug use or construction of episodes of drug use). The numerator of the fifth point prevalence estimate represented the number of defined daily doses (DDDs) instead of the number of patients filling a prescription. The first four point prevalences ranged from 11.0-12.1 per thousand. Prevalence ratio (male:female) was 1.2 for these methods. The fifth method resulted in an estimate similar to the other point prevalences (11.9 DDDs/1000 inhabitants). However, the prevalence ratio was 1.4 due to larger average number of DDDs prescribed to men. One year-prevalence was 4-5 per thousand higher than point prevalences. The comparison of these methods indicated that the choice of prevalence measure (point versus period prevalence) substantially influenced the prevalence estimate, whereas the influence of data handling was negligible. For standardization purposes in drug utilization research, we recommend estimating point prevalence instead of period prevalence. The various methods of data handling before estimating point prevalence yielded similar results and therefore we cannot recommend one specific method. However, defined daily doses should not be used to estimate (point) prevalences of drug use because this measure is significantly influenced by prescribed dosage regimens.

Pediatric Drug Formulations: A Review of Challenges and Progress

Children differ from adults in many aspects of pharmacotherapy, including capabilities for drug administration, medicine-related toxicity, and taste preferences. It is essential that pediatric medicines are formulated to best suit a child’s age, size, physiologic condition, and treatment requirements. To ensure adequate treatment of all children, different routes of administration, dosage forms, and strengths may be required. Many existing formulations are not suitable for children, which often leads to off-label and unlicensed use of adult medicines. New regulations, additional funding opportunities, and innovative collaborative research initiatives have resulted in some recent progress in the development of pediatric formulations. These advances include a paradigm shift toward oral solid formulations and a focus on novel preparations, including flexible, dispersible, and multiparticulate oral solid dosage forms. Such developments have enabled greater dose flexibility, easier administration, and better acceptance of drug formulations in children. However, new pediatric formulations address only a small part of all therapeutic needs in children; moreover, they are not always available. Five key issues need to be addressed to stimulate the further development of better medicines for children: (1) the continued prioritization of unmet formulation needs, particularly drug delivery in neonates and treatment gaps in pediatric cancers and childhood diseases in developing countries; (2) a better use of existing data to facilitate pediatric formulation development; (3) innovative technologies in adults that can be used to develop new pediatric formulations; (4) clinical feedback and practice-based evidence on the impact of novel formulations; and (5) improved access to new pediatric formulations.

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.

Switching from originator brand medicines to generic equivalents in selected developing countries: how much could be saved?

OBJECTIVES In low- and middle-income countries, patients and reimbursement agencies that purchase medicines in the private sector pay more for originator brands when generic equivalents exist. We estimated the savings that could be obtained from a hypothetical switch in medicine consumption from originator brands to lowest-priced generic equivalents for a selection of medicines in 17 countries. METHODS In this cost minimization analysis, the prices of originator brands and their lowest-priced generic equivalents were obtained from facility-based surveys conducted by using a standard methodology. Fourteen medicines most commonly included in the surveys, plus three statins, were included in the analysis. For each medicine, the volume of private sector consumption of the originator brand product was obtained from IMS Health, Inc. Volumes were applied to the median unit prices for both originator brands and their lowest-priced generics to estimate cost savings. Prices were adjusted to 2008 by using consumer price index data and were adjusted for purchasing power parity. RESULTS For the medicines studied, an average of 9% to 89% could be saved by an individual country from a switch in private sector purchases from originator brands to lowest-priced generics. In public hospitals in China, US

Evaluation of post-authorization safety studies in the first cohort of EU Risk Management Plans at time of regulatory approval.

370 million could be saved from switching only four medicines, saving an average of 65%. Across individual medicines, average potential savings ranged from 11% for beclometasone inhaler to 73% for ceftriaxone injection. CONCLUSIONS Substantial savings could be achieved by switching private sector purchases from originator brand medicines to lowest-priced generic equivalents. Strategies to promote generic uptake, such as generic substitution by pharmacists and increasing confidence in generics by professionals and the public, should be included in national medicines policies.