Quantitative Measurement of the Direct Public Health Impact of Medicines Withdrawals in Europe: Development of a Modelling Method and Proof-of-Concept Study to Estimate the Morbidity and Mortality Prevented by Regulatory Action.

Abstract

Removing medicines from market may benefit public health by preventing adverse drug reactions (ADRs), which should be quantified. This study's aim was to identify a model to quantify the impact of medicines' marketing authorisation (MA) withdrawal and revocation in terms of preventing morbidity and mortality. MA withdrawals and revocations for safety reasons in France, Germany and/or the United Kingdom between July 2012 and December 2016 were identified for prescription medicines. Annual exposure was estimated for each medicine, using IQVIA Medical Research Data (IMRD)-France, IMRD-Germany and IMRD-UK primary care electronic health record databases. European Medicines Agency records provided reasons for regulatory action for each medicine. Absolute risks of ADRs which led to MA withdrawal were estimated for patients exposed to each medicine by systematic review of quantitative research. Public health impact, expressed as annual number of ADRs avoided, was estimated by modelling exposure and ADR risk. Four MA withdrawals and two revocations met study inclusion criteria. Each product's usage decreased following MA withdrawal or revocation. Absolute risk for ADRs was 0.1%-41.25%. To estimate impact of each withdrawal or revocation, its average annual exposure within each IMRD population was multiplied by the absolute risk to give the crude number of ADRs prevented annually due to regulatory action. This model quantifies the public health impact of MA withdrawal and revocation in terms of serious morbidity, resulting from eliminated or reduced usage of medicines. This method can be applied to products in other settings to quantify the impact of other pharmacovigilance actions.