Impact of 2018 EU Risk Minimisation Measures and Revised Pregnancy Prevention Programme on Utilisation and Prescribing Trends of Medicinal Products Containing Valproate: An Interrupted Time Series Study

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  • Shahab Abtahi
  • Romin Pajouheshnia
  • Carlos E. Durán
  • Judit Riera-Arnau
  • Magdalena Gamba
  • Ema Alsina
  • Vjola Hoxhaj
  • Claudia Bartolini
  • Sarah Brøgger Kristiansen
  • Jeremy Brown
  • Patricia Garcia-Poza
  • Helga Gardarsdottir
  • Rosa Gini
  • Anna Girardi
  • Emily Holthuis
  • Consuelo Huerta
  • Luisa Ibánez
  • Giorgio Limoncella
  • Mar Martín-Pérez
  • Olga Paoletti
  • Giuseppe Roberto
  • Patrick Souverein
  • Karin M.A. Swart
  • Kevin Wing
  • Miriam Sturkenboom
  • Olaf Klungel

Introduction: Due to established teratogenicity of valproates, the EU risk minimisation measures (RMMs) with a pregnancy prevention programme (PPP) for valproate were updated in March 2018. Objectives: To investigate the effectiveness of the 2018 EU RMMs on valproate utilisation in five European countries/regions. Methods: A multi-database, times series study of females of childbearing potential (12–55 years) was conducted using electronic medical records from five countries/regions (01.01.2010–31.12.2020): Denmark, Tuscany (Italy), Spain, the Netherlands, and the UK. Clinical and demographic information from each database was transformed to the ConcePTION Common Data Model, quality checks were conducted and a distributed analysis was performed using common scripts. Incident and prevalent use of valproate, proportion of discontinuers and switchers to alternative medicine, frequency of contraception coverage during valproate use, and occurrence of pregnancies during valproate exposure were estimated per month. Interrupted time series analyses were conducted to estimate the level or trend change in the outcome measures. Results: We included 69,533 valproate users from 9,699,371 females of childbearing potential from the five participating centres. A significant decline in prevalent use of valproates was observed in Tuscany, Italy (mean difference post-intervention −7.7%), Spain (−11.3%), and UK (−5.9%) and a non-significant decline in the Netherlands (−3.3%), but no decline in incident use after the 2018 RMMs compared to the period before. The monthly proportion of compliant valproate prescriptions/dispensings with a contraceptive coverage was low (<25%), with an increase after the 2018 RMMs only in the Netherlands (mean difference post-intervention 12%). There was no significant increase in switching rates from valproates to alternative medicine after the 2018 intervention in any of the countries/regions. We observed a substantial number of concurrent pregnancies during valproate exposure, but with a declining rate after the 2018 RMMs in Tuscany, Italy (0.70 per 1000 valproate users pre- and 0.27 post-intervention), Spain (0.48 and 0.13), the Netherlands (0.34 and 0.00), and an increasing rate in UK (1.13 and 5.07). Conclusion: There was a small impact of the 2018 RMMs on valproate use in the studied European countries/regions. The substantial number of concurrent pregnancies with valproate exposure warrants a careful monitoring of implementation of the existing PPP for valproate in clinical practice in Europe, to see if there is any need for additional measures in the future.

Original languageEnglish
JournalDrug Safety
Issue number7
Pages (from-to)689-702
Publication statusPublished - 2023

Bibliographical note

Funding Information:
The research leading to these results was conducted as part of the activities of the EU PE&PV (Pharmacoepidemiology and Pharmacovigilance) Research Network, which is a public academic partnership coordinated by the Utrecht University, the Netherlands. The project has received support from the European Medicines Agency under the Framework service contract nr EMA/2018/28/PE. The content of this paper expresses the opinion of the authors and may not be understood or quoted as being made on behalf of or reflecting the position of the European Medicines Agency or one of its committees or working parties.

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