The French Levothyrox® crisis: We did the best we could but…

Patient's reporting of adverse drug reactions: Which added value in 2023?

Several studies were focused on the qualitative and quantitative analysis of serious adverse drug reactions (ADRs) leading to hospitalisation or death. These figures do not take into account ADRs in ambulatory patients affecting their quality of life. Patient reporting has the advantages of bringing novel information about ADRs. It provides a more detailed description of ADRs, and reports about different drugs and system organ classes when compared with health care professional (HCP) reporting. A certain amount of information is crucial in order to determine the drug-reaction relationship. European regulation and patient support programs have contributed widely to increased patient reporting but the quality of ADR reports is still unequal from one country to another. Patient reports of ADRs have contributed enormously to pharmacovigilance signal detection in a number of ways. Over the last decades, countries have developed dedicated websites for direct patient reporting. The increasing involvement of patients in ADR reporting activities facilitated by a web portal was confirmed by some studies. Patients are now recognised as having a legitimate part to play in the decision-making process. The contribution of patient reports to drug safety was acknowledged and consolidated by European Union (EU) PV legislation in 2012 aiming to involve patients more actively, nowadays called "patient centricity in pharmacovigilance". Patient organisations are involved in regulatory issues and collaborate with health institutions on the development of guidelines. However, some studies suggested that a substantial number of patient organisations have potential financial conflicts of interest but limited disclosure practices. Pharmaceutical companies integrate into patient associations, particularly for chronic diseases by different strategies: educational therapeutic or observance support programs. The question of conflict of interest of patient associations is important requiring better transparency.

Impact of Covid-19 Vaccination on Spontaneous Pharmacovigilance Reporting in France

INTRODUCTION

In 2021, the massive Covid-19 vaccination campaign in France was accompanied by an intensified pharmacovigilance monitoring of their potential adverse drug reactions. The importance of this reporting might have led to an important selective reporting and overloading of Pharmacovigilance Centres, delaying the recording of some reports in the national pharmacovigilance database. In this context, we aimed to evaluate the impact of the Covid-19 vaccination campaign in France and related reports on spontaneous reporting of adverse drug reactions that were not related to the Covid-19 vaccine.

METHODS

We performed time-series analyses considering the monthly number of adverse drug reactions reported between January 1, 2018 and April 30, 2022 using the French Pharmacovigilance database. The impact of the Covid-19 vaccination campaign on the monthly reporting not Covid-19 vaccine related was estimated using interrupted time-series. January 2021, marking the start of the campaign, was the intervention date in the models. Analyses were run globally first considering all adverse drug reaction reports, and second according to notifier type and to case seriousness.

RESULTS

We included 170,294 reports registered in the French Pharmacovigilance database between January 1, 2018 and April 30, 2022 that were not Covid-19 vaccine-related. Among these, 77,067 (45.3%) were serious and 146,683 (86.1%) had been reported by health care professionals. The campaign start was associated with a nearly 35.0% decrease in average monthly reporting that was not Covid-19 vaccine-related, with a significant level decrease in the monthly number of reports of -658.0 (p < 10-3) immediately after the vaccination campaign start and a subsequent slope decrease of -50.0 (p < 10-3). This decrease was mainly due to a significant level and slope decrease (level: -739.2 p < 10-3; slope: -39 [p < 10-2]) for health care professional reports. A similar level decrease was found for the monthly number of both serious and non-serious reports (-402.3, p < 10-3; and -311.9, p = 10-2, respectively). According to the ATC 1 level, the decrease in the monthly number of reports showed similar patterns for all drugs. However, a potential increase in the number of serious reports suspecting antineoplastic and immunomodulating drugs (ATC L) or drugs targeting blood was observed (ATC B).

CONCLUSION

Our study showed a significant impact of the Covid-19 campaign vaccination in the reporting of adverse drug reactions that were not Covid-19 vaccine-related, of roughly 35%. This leads to a loss of information regarding the monitoring of drug safety that could have impacted the system capacity to detect safety signals for drugs other than Covid-19 vaccines.

Validation of Artificial Intelligence to Support the Automatic Coding of Patient Adverse Drug Reaction Reports, Using Nationwide Pharmacovigilance Data

INTRODUCTION

Adverse drug reaction reports are usually manually assessed by pharmacovigilance experts to detect safety signals associated with drugs. With the recent extension of reporting to patients and the emergence of mass media-related sanitary crises, adverse drug reaction reports currently frequently overwhelm pharmacovigilance networks. Artificial intelligence could help support the work of pharmacovigilance experts during such crises, by automatically coding reports, allowing them to prioritise or accelerate their manual assessment. After a previous study showing first results, we developed and compared state-of-the-art machine learning models using a larger nationwide dataset, aiming to automatically pre-code patients' adverse drug reaction reports.

OBJECTIVES

We aimed to determine the best artificial intelligence model identifying adverse drug reactions and assessing seriousness in patients reports from the French national pharmacovigilance web portal.

METHODS

Reports coded by 27 Pharmacovigilance Centres between March 2017 and December 2020 were selected (n = 11,633). For each report, the Portable Document Format form containing free-text information filled by the patient, and the corresponding encodings of adverse event symptoms (in Medical Dictionary for Regulatory Activities Preferred Terms) and seriousness were obtained. This encoding by experts was used as the reference to train and evaluate models, which contained input data processing and machine-learning natural language processing to learn and predict encodings. We developed and compared different approaches for data processing and classifiers. Performance was evaluated using receiver operating characteristic area under the curve (AUC), F-measure, sensitivity, specificity and positive predictive value. We used data from 26 Pharmacovigilance Centres for training and internal validation. External validation was performed using data from the remaining Pharmacovigilance Centres during the same period.

RESULTS

Internal validation: for adverse drug reaction identification, Term Frequency-Inverse Document Frequency (TF-IDF) + Light Gradient Boosted Machine (LGBM) achieved an AUC of 0.97 and an F-measure of 0.80. The Cross-lingual Language Model (XLM) [transformer] obtained an AUC of 0.97 and an F-measure of 0.78. For seriousness assessment, FastText + LGBM achieved an AUC of 0.85 and an F-measure of 0.63. CamemBERT (transformer) + Light Gradient Boosted Machine obtained an AUC of 0.84 and an F-measure of 0.63. External validation for both adverse drug reaction identification and seriousness assessment tasks yielded consistent and robust results.

CONCLUSIONS

Our artificial intelligence models showed promising performance to automatically code patient adverse drug reaction reports, with very similar results across approaches. Our system has been deployed by national health authorities in France since January 2021 to facilitate pharmacovigilance of COVID-19 vaccines. Further studies will be needed to validate the performance of the tool in real-life settings.

Why Were More Than 200 Subjects Required to Demonstrate the Bioequivalence of a New Formulation of Levothyroxine with an Old One?

At the request of French Regulatory Authorities, a new formulation of Levothyrox^® was licensed in France in 2017, with the objective of avoiding the stability deficiencies of an existing licensed formulation. Before launching the new formulation, an average bioequivalence (ABE) trial was conducted, having enrolled 204 subjects and selected for interpretation a narrow a priori bioequivalence range of 0.90-1.11. Bioequivalence was concluded. In a previous publication, we questioned the ability of an ABE trial to guarantee the switchability within patients of the new and old levothyroxine formulations. It was suggested that the two formulations should be compared using the conceptual framework of individual bioequivalence. The present paper is a response to those claiming that, despite the fact that ABE analysis does not formally address the switchability of the two formulations, future patients will nevertheless be fully protected. The basis for this claim is that the ABE study was established in a large trial and analyzed using a stringent a priori acceptance interval of equivalence. These claims are questionable, because the use of a very large number of subjects nullifies the implicit precautionary intention of the European guideline when, for a Narrow Therapeutic Index drug, it recommends shortening the a priori acceptance interval from 0.80-1.25 to 0.90-1.11.

Interest of a general practitioner pharmacovigilance network to provide drug information: A comparative study in France

INTRODUCTION

Since 2015, Toulouse University PharmacoVigilance Center (TUPVC) set up a pharmacovigilance (PV) general practitioner (GP) network, called PharmacoMIP-MG. A clinical research assistant (CRA) moves to the office of GPs included in the PharmacoMIP-MG network (PMIP-GPs). There, he collects the adverse drug reaction (ADR) reports and drug-related questions. This additional support is not available to GPs not included in the PV network (NoPMIP-GPs) who have to ask drug questions spontaneously to the TUPVC.

OBJECTIVE

The objective of this study was to compare the number and characteristics of drug questions between PMIP-GPs and NoPMIP-GPs.

METHODS

All questions asked by GPs to the TUPVC from 01 Jan 2015 to 31 Dec 2017 were reviewed. Questions were classified into two groups: "general" and "related to a patient". The "related to a patient" category was divided in three subgroups: "ADRs", Drug-Drug Interactions and "Drug Management". Drugs were classified according to anatomical therapeutic chemical (ATC) classification. For comparisons, Wilcoxon test, Chi² test or Fisher test were used.

RESULTS

During the study period, the CRA collected 293 questions from the 165 PMIP-GPs. TUPVC received 333 questions asked spontaneously by the 3400 NoPMIP-GPs. PMIP-GPs asked significantly 3 times more questions than NoPMIP-GPs. Most of the GP questions were classified in the "related to a patient" category (74.9%). When we compared the proportion of "related to a patient" to "general" questions, there was no statistically significant difference between PMIP-GPs and NoPMIP-GPs. PMIP-GPs asked more questions about "ADRs", but less on "Drug Management" and or "Drug-Drug Interactions". The drugs most frequently involved were amiodarone, rivaroxaban and levothyroxine.

CONCLUSION

This is the first study about GPs' drug-related questions asked to a PV center. We found that an organization, such as a CRA-GP "face to face" visit, increased the number of drug questions. This kind of organization should be developed in order to improve independent drug information outreach.

Does spontaneous adverse drug reactions' reporting differ between different reporters? A study in Toulouse Pharmacovigilance Centre

INTRODUCTION

In France since 2011, report of adverse drug reactions (ADRs) has been extended to patients (and patients' associations) who can declare directly ADRs to their regional pharmacovigilance centre. In pharmacovigilance, informativeness of ADRs reports is important to improve signal's detection. The present study was performed to compare the quality of patients', physicians and community pharmacists' reports.

METHODS

We performed a retrospective study investigating the quality of patients', physicians and community pharmacies' ADRs reported to Toulouse University PharmacoVigilance Centre (TUPVC) from January 2014 to June 2017. We used mandatory and non-mandatory criteria, as defined by European Medicines Agency. Reports' quality was defined as "satisfactory" when more than 90% of items were completed. We also compared reports' quality according to ADRs seriousness and the used reporting tools (email or the mobile app VigiBip^®).

RESULTS

The number of reports to TUPVC increased between 2014 and 2016 (+51%) for patients and remained stable for pharmacists and physicians. According to the mandatory criteria, quality of the investigated reports was "satisfactory" (more than 90% of the items filled) whatever the reporter and without significant differences between reporters. For the non-mandatory criteria, clinical description of ADRs and ADRs' outcome were only filled over 90%. Significant differences were observed between the different reporters: community pharmacists informed better clinical description, ADR outcome and concomitant drugs versus both patients and physicians. Physicians informed better medical history and biological data whereas patients informed medical history and other aetiologies better than pharmacists and clinical description of ADRs better than physicians.

CONCLUSION

The present study failed to show differences between pharmacies', physicians' and patients' ADRs reports, for the mandatory criteria. However, significant differences were found for non-mandatory criteria with drug data more filled by pharmacists and medical ones more by physicians and patients.