Co-dispensing of contraindicated medications in patients using cisapride in Italy

The Use of Real-World Data to Assess the Impact of Safety-Related Regulatory Interventions

The regulation of medicines seeks to ensure the efficacy, safety, and quality of prescription and non-prescription medicines. Given that the conditions under which a medicine's benefits outweigh its risks are complex, it is essential that communications about the safe and effective use of medicines be clear and actionable. Assessing the impact of interventions to improve the safe and effective use of medicines is a developing area, and one in which real-world data are playing an increasingly important role. Although real-world data are commonly used to assess the impact of regulatory interventions, there are several areas where their use could be improved. Specific areas for improvement include assessing regulatory interventions across a wider range of medicines, rather than concentrating on a relatively few therapeutic areas; assessing more clinically relevant outcomes rather than relying on measures such as changes in the number of prescriptions, which may not always correlate with the desired impact; assessing the potential unintended or negative consequences of regulatory interventions; applying methods to address potential confounders; assessing long-term, rather than just short-term, impacts of an intervention; increasing the use of comparator groups, when feasible; and evaluating the impact of regulatory interventions from multiple dimensions, rather than from a single dimension. Expanded use of real-world data could inform some of these efforts, although data sources beyond administrative claims data will likely be necessary to achieve all these goals.

Do drug-related safety warnings have the expected impact on drug therapy? A systematic review

PURPOSE

The need for drug-related safety warnings is undisputed, and their impact should also be evaluated. This systematic review investigates and assesses the impact of safety warnings on drug therapy.

METHODS

Studies published in English between January 1998 and December 2018 were searched in EMBASE and MEDLINE, complemented by manual search. Randomised controlled trials, cohort studies with a before/after component, and case-control studies were included, selected to predefined criteria, and assessed for their reporting and methodological quality.

RESULTS

Out of 7454 references identified, 72 studies were included. A total of 28/72 (39%) studies described the impact of safety warnings on drug therapy as being effective, whereas 12/72 (17%) studies did not. Further, 26/72 (36%) studies described a partial implementation of the warnings (one part of the warning had an impact on drug therapy and another did not). Unintended effects were investigated in 6/72 (8%) studies. While 34 (47%) studies examined safety warnings on psychotropic drugs using an interrupted time series (ITS) design (53%), a before/after (26%), and a time series design (21%), 38 (53%) studied other substances using an ITS design (34%), a before/after (40%), and a time series design (26%). The proportion of an effective impact on drug therapy was lower in the "psychotropic drugs" group (23%) than in the "others" group (53%).

CONCLUSION

Drug-related safety warnings induce intended and unintended effects. The included studies are of broadly varying methodological quality. To better compare their effectiveness, studies should be conducted using standardised procedures.

The effectiveness of risk communication regarding drug safety information: a nationwide survey by the Japanese public health insurance claims data

WHAT IS KNOWN AND OBJECTIVE

We evaluated the effectiveness of warning letters published by the pharmaceutical regulatory agency in Japan on communication of drug safety and risk by quantitative analysis of the national health insurance claims database (NHICD). We then explored what factors may have affected risk communication.

METHODS

We measured the implementation rate of the hepatitis virus-monitoring test among methotrexate (MTX)-treated patients; a warning letter had been issued regarding the use of MTX, as it apparently activates the hepatitis virus. Data from the NHICD, which include 99·3% of Japanese residents, were used. A total of 4,933,481 patients with rheumatoid arthritis (RA) (January-June, 2010) were the focus of this study.

RESULTS

The implementation rate of the hepatitis virus-monitoring test increased from 1·4% before to 1·8% after the warning letter announcement. Logistic regression analysis suggested that the installation of a drug information management room is one of the important factors affecting risk communication. Further analysis revealed that the hepatitis virus monitoring rates in hospitals without drug information management rooms increased from 2·3% to 4·1% due to the issue of the warning letter.

WHAT IS NEW AND CONCLUSION

The warning letter from the regulatory agency plays an important role in risk communication in hospitals without drug information management rooms.

Methodological gaps in the assessment of risk minimization interventions: a systematic review

INTRODUCTION

Since the introduction of therapeutic risk management regulatory guidance, an increase in the number of risk minimization interventions (RMIs) published in the literature has been observed. Methods used to evaluate their effectiveness remain, however, poorly examined.

OBJECTIVE

This paper aimed to conduct a literature review on the methods of evaluation of effectiveness of RMIs and to identify methodological gaps.

METHODS

The search was conducted using MEDLINE and Embase between 1 January 2000 and 31 December 2010, and updated on 1 April 2013. The following characteristics were extracted from each study: target population for the RMI, target population for the assessment of effectiveness, study design, data sources, and effectiveness outcome(s).

RESULTS

A total of 188 unique RMIs were identified in the literature, of which effectiveness was evaluated in only 65 (34.6%) at the time of publication. The largest proportion of studies reviewed (n = 49, 75.4%) attempted to evaluate changes in behavior through prescribing or laboratory test practices. One quarter of studies evaluated the effect of RMIs on the occurrence of adverse events. Only a minority of studies used robust designs, such as randomized controlled trials (n = 6, 9.2%) or a quasi-experimental design with a parallel comparison group (n = 8, 12.3%).

CONCLUSION

Lack of robust methodological design used in published studies on RMI effectiveness evaluation is an important methodological gap in the evaluation of RMI effectiveness. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.

Prescribing of rosiglitazone and pioglitazone following safety signals: analysis of trends in dispensing patterns in the Netherlands from 1998 to 2008

BACKGROUND

Relevant safety signals in the EU are regularly communicated in so-called 'Direct Healthcare Professional Communications' (DHPCs) or European Medicines Agency (EMA) press releases. Trends of a decrease in the use of rosiglitazone following regulatory safety warnings have been described in the US. In the EU, however, relatively little is known about dispensing patterns following DHPCs or other safety signals such as EMA press releases.

OBJECTIVE

The objective of this study was to analyse trends in dispensing patterns of rosiglitazone and pioglitazone following DHPCs and EMA press releases in the EU member state, the Netherlands.

METHODS

Data for this study were obtained from the PHARMO Record Linking System, which includes drug dispensing records from community pharmacies of approximately 2.5 million individuals in the Netherlands. Over the period 1998-2008 an auto-regressive, integrated, moving average model (ARIMA) was fitted. The DHPC letters or EMA press releases were used as determinants. Adjustments were made for publication of certain literature. Stratification was performed for dispensings prescribed by general practitioners (GPs) and those prescribed by specialists.

RESULTS

For rosiglitazone, four EMA press releases and two DHPCs were issued; for pioglitazone, one DHPC was issued. The number of rosiglitazone dispensings prescribed by GPs decreased significantly after publication of DHPCs and EMA press releases concerning the risk of macular oedema and risk of fractures (both p-values 0.001). The number of rosiglitazone dispensings decreased statistically significantly after publication of EMA press releases 2 and 3 concerning cardiovascular risks but not for EMA press release 4. Adjustment for certain publications in the literature reduced the effect of communicated safety issues on the proportion of dispensings.

CONCLUSIONS

Although it is difficult to disentangle the effect of DHPCs and EMA press releases from the effect of reports published in the literature, our results suggest that prescribers may react to such safety communications.

A decade of safety-related regulatory action in the Netherlands: a retrospective analysis of direct healthcare professional communications from 1999 to 2009

BACKGROUND

As pre-approval trials are inherently limited in assessing the complete benefit-risk profile of a new drug, serious safety issues may emerge once a drug gains widespread use after approval. Regulators face the dilemma of balancing timely market access with the need for complete data on risks. This challenge has led to a life-cycle approach but, so far, few data are available on post-approval safety issues requiring regulatory action.

OBJECTIVE

The aim of this study is to determine the frequency, timing and nature of safety issues that necessitated safety-related regulatory action in the form of a Direct Healthcare Professional Communication (DHPC) issued by pharmaceutical companies in collaboration with the Dutch Medicines Evaluation Board during the past decade.

METHODS

All DHPCs issued in the Netherlands from 1 January 1999 to 1 January 2009 were retrospectively collected from the national regulatory authorities. Elapsed time between the approval date and the issue of the DHPC was determined. Characteristics of the action including the nature of the safety issue (according to Medical Dictionary for Regulatory Activities [MedDRA] terminology), type of drug and procedural aspects of the regulatory action taken were reviewed. DHPC characteristics were tabulated and explorative non-parametric tests were performed to study the effect of safety issue, drug class, drug type, orphan drug and first-in-class status on elapsed time from approval to the DHPC.

RESULTS

157 DHPCs were issued concerning 112 different active substances, approximately 9% (112/1200) of active substances available in the Netherlands in 2007. The number of DHPCs issued increased by 2.1 (95% CI 1.2, 3.1; p < 0.001) DHPCs per year over the past decade, reaching a total of 25 in 2008. The median time between approval and DHPC was 5.3 years (range 0.13-48 years). No significant trend in elapsed time to DHPC was observed in relation to the studied years (p = 0.06). One-third of all DHPCs were issued in the first 3 years after approval, but 27% (n = 43/157) of the DHPCs were issued 10 or more years after approval. Timing of DHPCs differed depending on safety issue, drug class, drug type and orphan drug status. DHPCs mostly concerned adverse events in the system organ class of 'cardiac disorders' (15%), 'injury, poisoning and procedural complications' (13%) and 'general disorders and administration site conditions' (10%). In ten cases the drug was eventually withdrawn. Withdrawal occurred a median duration of 2.4 years after registration (range of 1.5-48 years) and was most frequently due to cardiac disorders (including QT interval prolongation; four occasions) and hepatobiliary disorders (two occasions).

CONCLUSIONS

In the past decade, the number of DHPCs has increased over time. This is likely caused by a multitude of factors: increased risk awareness by the public, media, regulators and other stakeholders; the type of drugs approved, such as orphan drugs and biologicals; and the regulatory process, including conditional approvals. The number of DHPCs may in the future increase further with the possibility of screening large epidemiological databases proactively for adverse drug events. Nine percent of all marketed drugs required a safety-related action. Regulatory action is taken shortly (<3 years) after market approval nearly as often as after intermediate (3-10 years) and long-term (>10 years) market exposure. These findings underline the need for risk management during the whole life cycle of a drug.

Prevalence and predictors of potential drug-drug interactions in Regione Emilia-Romagna, Italy

BACKGROUND AND OBJECTIVE

Drug-drug interactions (DDIs) are preventable medication errors associated with potentially serious adverse events and death. Several studies have examined the prevalence of potential DDIs among ambulatory patients in various countries. Limited recent data on the prevalence of potential DDIs in Italy are available in the medical literature. The objective of this study was to estimate the prevalence of clinically important potential DDIs among the approximately 4 million residents of Regione Emilia-Romagna (RER), Italy, and to examine possible predictors of potential DDI exposure.

METHODS

A retrospective follow-up study of 2004 outpatient prescription data from RER was conducted. A previously published list of clinically important potential DDIs was refined to include only pairs of drugs in which both drugs were reimbursed by the 2004 Italian National Formulary. A potential DDI was defined as the presence of a minimum 5-day overlap in days supply for drugs in an interacting pair. The 1-year period prevalence of each potential DDI was quantified. A logistic regression analysis was conducted to examine patient characteristics as predictors of potential DDIs.

RESULTS AND DISCUSSION

The list of clinically important potential DDIs included 12 drug pairs that could be captured using the RER database. These 12 potential DDIs occurred 8894 times in the RER population in 2004. The most commonly identified potentially interacting medication pairs were warfarin and non-steroidal anti-inflammatory drugs (6824 cases), theophylline/aminophylline and ciprofloxacin/fluvoxamine (930), and warfarin and barbiturates (567). Odds of exposure were highest among those aged 65 years or older, males, and those with more chronic conditions. Odds of exposure increased 1.39 times with each addition of a prescription medication.

CONCLUSION

A substantial number of clinically important potential DDIs were identified, particularly among warfarin users. Awareness of the most prevalent potential DDIs can help practitioners prevent concomitant use of these dangerous medication combinations.