[COVID-19 and adenovirus vaccines: French experience of enhanced pharmacovigilance]

As part of the COVID-19 vaccination campaign, the National Agency for the Safety of Medicines and Health Products and all 31 regional pharmacovigilance centers were mobilized in an exceptional reinforced vaccine pharmacovigilance surveillance system. Concerning adenovirus vaccines, Vaxzévria® and Jcovden®, this national system, based on the daily analysis of notified cases of adverse events, has allowed the early identification of safety signals, some of which have been validated, others still under analysis, common to mRNA vaccines or more specific of adenovirus vaccines such as Vaccine Induced Immune Thrombocytopenia. Complementing european and international actions, this follow-up has contributed to a better definition of the safety profile of these vaccines and has led to redefine the vaccine strategy in our country. Although today these two vaccines have no longer place in the national vaccine strategy, they are still used in other countries, where the experience acquired could be useful and will contribute to fuel the reflection on future therapies involving viral vectors.