Lessons Learned on Observed-to-Expected Analysis Using Spontaneous Reports During Mass Vaccination.

During the COVID-19 vaccination campaign, observed-to-expected analysis was used by the European Medicines Agency to contextualise data from spontaneous reports to generate real-time evidence on emerging safety concerns that may impact the benefit-risk profile of COVID-19 vaccines. Observed-to-expected analysis compares the number of cases spontaneously reported for an event of interest after vaccination ('observed') to the 'expected' number of cases anticipated to occur in the same number of individuals had they not been vaccinated. Observed-to-expected analysis is a robust methodology that relies on several assumptions that have been described in regulatory guidelines and scientific literature. The use of observed-to-expected analysis to support the safety monitoring of COVID-19 vaccines has provided valuable insights and lessons on its design and interpretability, which could prove to be beneficial in future analyses. When undertaking an observed-to-expected analysis within the context of safety monitoring, several aspects need attention. In particular, we emphasise the importance of stratified and harmonised data collection both for vaccine exposure and spontaneous reporting data, the need for alignment between coding dictionaries and the crucial role of accurate background incidence rates for adverse events of special interest. While these considerations and recommendations were determined in the context of the COVID-19 mass vaccination setting, they are generalisable in principle.

The Role of the European Medicines Agency in the Safety Monitoring of COVID-19 Vaccines and Future Directions in Enhancing Vaccine Safety Globally.

The European Union (EU) regulatory network was at the forefront of the safety monitoring of COVID-19 vaccines during the pandemic. An unprecedented number of case reports of suspected adverse reactions after vaccination called for huge efforts for the assessment of this safety information, to ensure that any possible risks were detected and managed as early as possible, while ruling out coincidental but temporally related adverse health outcomes. We describe the role of the European Medicines Agency alongside the EU regulatory network in the safety monitoring of the COVID-19 vaccines, and provide an insight into challenges, particularities and outcomes of the scientific assessment and regulatory decisions in the complex, dynamic international environment of the pandemic. We discuss the flexible procedural tools that were used to ensure an expedited scientific assessment of safety issues, and subsequent updates of the product information (i.e., labelling) when available evidence (e.g., spontaneous reports, findings from observational studies and/or scientific literature) suggested that causal association is at least a reasonable possibility. The safety monitoring was accompanied by enhanced transparency measures, proactive communication, and easy access to information, which played a key role in public reassurance. The pandemic has been a powerful booster for worldwide collaboration, exchange of information and work-sharing. The safety monitoring of COVID-19 vaccines continues, and the lessons learned will be applied in future safety reviews, as well as future health emergencies.

Safety Monitoring of COVID-19 Vaccines: Perspective from the European Medicines Agency.

Prior to deployment of coronavirus disease 2019 (COVID-19) vaccines in the European Union in 2021, a high vaccine uptake leading to an unprecedented volume of safety data from spontaneous reports and real-world evidence, was anticipated. The European Medicines Agency (EMA) implemented specific activities to ensure enhanced monitoring of emerging vaccine safety information, including intensive monitoring of reports of adverse events of special interest and the use of observed-to-expected analyses. The EMA also commissioned several independent observational studies using a large network of electronic healthcare databases and primary data collection via mobile and web-based applications. This preparedness was key for two high-profile safety signals: thrombosis with thrombocytopenia syndrome (TTS), a new clinical entity associated with adenovirus-vectored vaccines, and myocarditis/pericarditis with messenger RNA vaccines. With no existing case definition nor background rates, the signal of TTS posed particular challenges. Nevertheless, it was rapidly identified, evaluated, contextualized and the risk minimized thanks to close surveillance and an efficient use of available evidence, clinical expertise and flexible regulatory tools. The two signals illustrated the complementarity between spontaneous and real-world data, the former enabling rapid risk identification and communication, the latter enabling further characterization. The COVID-19 pandemic has tremendously enhanced the development of tools and methods to harness the unprecedented volume of safety data generated for the vaccines. Areas for further improvement include the need for better and harmonized data collection across Member States (e.g., stratified vaccine exposure) to support signal evaluation in all population groups, risk contextualization, and safety communication.

Assuring Access to Safe Medicines in Pregnancy and Breastfeeding.

Scientists and regulators in Europe and the United States continue to seek methods and strategies to improve knowledge on rational use of medicines for pregnant and breastfeeding populations, an important subset of women's health. Regulatory agencies have made strides toward improvement, but much more is needed. Recognizing the importance of international collaboration, we have begun to consider how to address these important public health issues more globally. The health of the child begins with the health of the mother.

An algorithm to detect unexpected increases in frequency of reports of adverse events in EudraVigilance.

PURPOSE: The European Medicines Agency developed an algorithm to detect unexpected increases in frequency of reports, to enhance the ability to detect adverse events that manifest as increases in frequency, in particular quality defects, medication errors, and cases of abuse or misuse. METHODS: An algorithm based on a negative binomial time-series regression model run on 6 sequential observations prior to the monitored period was developed to forecast monthly counts of reports. A heuristic model to capture increases in counts when the previous 4 observations were null supplemented the regression. Count data were determined at drug-event combination. Sensitivity analyses were run to determine the effect of different methods of pooling or stratifying count data. Positive retrospective detections and positive predictive values (PPVs) were determined. RESULTS: The algorithm detected 8 of the 13 historical concerns, including all concerns of quality defects. The highest PPV (1.29%) resulted from increasing the lower count threshold from 3 to 5 and including literature reports in the counts. Both the regression model and the heuristic model components to the algorithm contributed to the detection of concerns. Sensitivity analysis indicates that stratification by commercial product reduces the PPV but suggests that pooling counts of related events may improve it. CONCLUSION: The results are encouraging and suggest that the algorithm could be useful for the detection of concerns that manifest as changes in frequency of reporting; however, further testing, including in prospective use, is warranted.

Usage of unpublished paediatric data.

The European Paediatric Regulation (EC No 1901/2006) has three main objectives: increasing the number of appropriate medicines for children, increasing information on these medicines and stimulating high-quality ethical research with children. To contribute to the information, pharmaceutical companies were required under article 45 of the Regulation to submit existing paediatric studies to regulatory authorities for review and update of the product information. Nearly, 19 000 study reports have been identified for a thousand active substances. The data are being assessed by member states' competent authorities in collaboration with European Medicines Agency (EMA). After 7 years, 262 active substances have been assessed, all of the 62 centrally approved and nearly 200 nationally approved medicines. The review so far has led to 16 new paediatric indications, of importance in addressing previously unmet needs, in particular, in younger age groups. The information is being made publicly available in an EMA database accessible directly or through the public face of the European Clinical Trials Register. This will increase awareness of existing data that are useful to researchers and other healthcare professionals, and contribute to avoiding unnecessary duplication of paediatric trials.

Enhanced Paediatric Pharmacovigilance at the European Medicines Agency: A Novel Query Applied to Adverse Drug Reaction Reports.

BACKGROUND: Databases of suspected adverse drug reactions (ADRs) are a cornerstone of pharmacovigilance. With increasing numbers of reports, additional statistical approaches are needed to better use the data. AIM: The present study was aimed at elucidating the European Medicines Agency's (EMA) use of a novel 'paediatric' query to analyse the data in its ADR database 'EudraVigilance'. METHODS: The proportional reporting ratio (PRR) is a measure of disproportionality for which the underlying principle is that a drug-event pair of interest is reported more often than expected relative to an independence model. The EMA's paediatric query, based on PRRs, was applied to the data in EudraVigilance to investigate the extent to which the known association between enalapril and renal toxicity was reflected in reported ADRs comparing children with adults and with adjustment for the effect of multiplicity. RESULTS: The comparison of PRRs for children (14.91, 95% confidence interval [CI] 13.05-17.04) versus adults (2.66, 95% CI 2.52-2.82) confirmed a higher risk of renal ADRs with enalapril when used in children compared with all other medicines and compared with adults. CONCLUSIONS: The EMA's paediatric query can be used to highlight an imbalance for a drug-event pair among ADRs for a medicine when used in children and as compared with adults. Applying the query in practice can help the EMA to decide on whether stand-alone paediatric medicine development is warranted, and which, if any, further studies are necessary. Ongoing evaluation of the query is contributing to the development of new methods and guidance.

Comparison between paediatric and adult suspected adverse drug reactions reported to the European medicines agency: implications for pharmacovigilance.

BACKGROUND: Databases systematically collecting reports of suspected adverse drug reactions (ADRs) are a cornerstone of pharmacovigilance in that they provide on-going large-scale surveillance in the 'real-world' setting. Several studies have provided data on ADRs in children reported to national databases. EudraVigilance (EV) is the European Medicines Agency's (EMA) web-based system for reporting and evaluating suspected ADRs. Due to requirements on pharmaceutical companies to report ADRs that originate both inside and outside Europe, the data in EudraVigilance are global in nature. As such, it is potentially a rich source of information for paediatric pharmacovigilance. AIM: The present study sought to provide a descriptive overview comparing ADRs involving children and adolescents aged less than 18 years with those involving adults reported to EudraVigilance across national boundaries. The results will serve as a baseline to explore whether lessons can be learned for paediatric pharmacovigilance. METHODS: All ADR reports received in EudraVigilance up to 13 June 2013 were analysed for overall numbers, age, gender, and geographic origin. Accurate age was determined when reported in valid format or calculated from the interval between date of birth and the reaction start date. The nature of the ADRs and the most frequently reported drug substances and drug event combinations were evaluated using Medical Dictionary for Regulatory Activities (MedDRA) 'preferred terms' (PTs) and 'system organ classes' (SOCs). The distribution over time of reported paediatric ADRs was also analysed. RESULTS: As of 13 June 2013, EudraVigilance contained 3,291,593 spontaneous reports, for 75.9 % of which accurate age was determined; 11.2 % of these were paediatric reports. Paediatric ADRs were more common than those in adults under the MedDRA SOCs 'general and administration site', 'nervous system', 'skin and subcutaneous' and 'infections and infestations'. For children, the three most frequently reported MedDRA PTs, i.e. pyrexia, vomiting and convulsion (13, 6 and 4 % of reports, respectively), accounted for a greater proportion of reports than the corresponding top three in adults, i.e. nausea, dyspnoea and pyrexia (4, 4 and 3 % of reports, respectively). The 20 most reported active substances (12 of which are vaccines) together accounted for 52 % of paediatric reports as compared with 28 % of adult reports. CONCLUSIONS: The present study applied a first-time approach to one of the largest databases worldwide of reported ADRs. It confirmed that reports of reactions in children were different to those in adults, not only in terms of reactions and drugs involved but also more concentrated around limited sets of reaction types and drugs. The possible causal association between a medicine or vaccine and the suspected ADR was not formally assessed in this study since the study analysed the characteristics of reported ADRs that were suspected and therefore not proven. However, the findings may help to identify pharmacovigilance activities that should be strengthened to reduce the burden of ADRs in children.