Comparative Analysis of Post-Authorization Measures for Advanced Medicinal Products Authorized in the European Union and in the United States of America Between 2009 and 2023.

In the current landscape, regulatory agencies face the challenge of reconciling timely authorizations for novel medicines addressing life-threatening conditions with thorough evaluations of their benefits and risks. This challenge is pronounced with advanced therapy medicinal products (ATMPs), where expedited approval mechanisms and orphan drug designations are often applied, making post-authorization measures a crucial mechanism to address uncertainties. We compared post-authorization measures imposed by the U.S. Food and Drug Administration and the European Medicines Agency on ATMPs approvals, from 2009 to 2023. A systematic extraction of FDA postmarketing requirements (PMRs) and EMA-imposed post-authorization measures (PAMs) from publicly available regulatory documents was conducted. Descriptive analysis focused on post-authorization measure categories, objectives, study designs, and their status and registration rates. A total of 15 ATMPs were approved in both jurisdictions over the study period. For these products, the EMA imposed 53 PAMs (34 Annex II conditions and 19 Specific Obligations), whereas the FDA imposed 27 PMRs. As of December 2023, 15 EMA-imposed PAMs were fulfilled, with no explicit fulfilments indicated for FDA PMRs. Both agencies promoted real-world data use in around half of the imposed PAMs (23 by EMA vs. 15 by FDA), marking regulators' growing recognition of Real-World Evidence for decision-making. This study highlights disparities between imposed PAMs: EMA imposed more PAMs, covering efficacy, safety, and quality aspects, while the FDA required fewer measures focusing on specific safety concerns. These discrepancies primarily reflect distinct regulatory structures and approaches to further post-authorization data collection between the EMA and FDA, rather than disparities in initial benefit/risk assessments.