Pharmacoepidemiology and public decision

Shaping the future of pharmacoepidemiology in France: Recommendations from the SFPT Pharmacoepidemiology Working Group

The drug authorization process is shifting towards a policy aimed at shortening time-to-market. While this policy facilitates early access to new treatments, it can also result in potentially insufficient knowledge of both efficacy and safety at the time of marketing. The latter is particularly true for long-term outcomes or in specific populations (e.g., children and the elderly). Yet, French pharmacoepidemiology is currently not designed to address these challenges, despite recognized expertise. In this context, we aim: (i) to define a strategy for strengthening pharmacoepidemiology in France; and (ii) to identify the associated human, technical, and financial requirements to ensure its success. In this paper, we present the French Pharmacoepidemiology Initiative (https://frenchpharmacoepi.org/), i.e. a network of independent academic teams to complement existing institutions. It will provide coordinated expertise and a workforce to meet national and regional needs for pharmacoepidemiological monitoring and drug-related decision-making. Leveraging the existing expertise of university hospital pharmacoepidemiology units would enable rapid operational deployment to inform the decisions and policies of national regulatory agencies.

Sudden Sensorineural Hearing Loss after COVID-19 Vaccination: A Review of the Available Evidence through the Prism of Causality Assessment

Sudden sensorineural hearing loss (SSNHL), a rare audiological condition that accounts for 1% of all cases of sensorineural hearing loss, can cause permanent hearing damage. Soon after the launch of global COVID-19 vaccination campaigns, the World Health Organization released a signal detection about SSNHL cases following administration of various COVID-19 vaccines. Post-marketing studies have been conducted in different countries using either pharmacovigilance or medico-administrative databases to investigate SSNHL as a potential adverse effect of COVID-19 vaccines. Here, we examine the advantages and limitations of each type of post-marketing study available. While pharmacoepidemiological studies highlight the potential association between drug exposure and the event, pharmacovigilance approaches enable causality assessment. The latter objective can only be achieved if an expert evaluation is provided using internationally validated diagnostic criteria. For a rare adverse event such as SSNHL, case information and quantification of hearing loss are mandatory for assessing seriousness, severity, delay onset, differential diagnoses, corrective treatment, recovery, as well as functional sequelae. Appropriate methodology should be adopted depending on whether the target objective is to assess a global or individual risk.