Issues with Tissues: Trends in Tissue-Engineered Products in Clinical Trials in the European Union.

Tissue-engineered products (TEPs) consist of engineered cells or tissues produced to regenerate, repair, or replace a dysfunctional, diseased, or absent human tissue. TEPs make up <5% of all advanced therapeutic medicinal products (ATMPs) in clinical trials and received 5.1% of ATMP-designated funding in trials in the European Union (EU) in 2019, highlighting the relatively low proportion of TEPs being developed. The realization of TEPs being marketed has yet to be fulfilled, with few products being approved. Since 2009, 90 TEP-based clinical trials have been undertaken in the EU. Of these 90, 25 were Phase I/II trials, 35 were Phase II, 28 were Phase III, and two were Phase IV trials. This review provides an overview of TEPs in development, identifying musculoskeletal, cardiovascular, and skin/connective tissue disorders as the main therapeutic areas of interest. Commercial sponsors have funded most trials, and a significantly higher proportion of late-phase trials. Furthermore, this study has identified a shift toward the use of allogeneic cells in TEPs and increased activity in the proportion of early phase trials listed. This indicates a renewed interest in TEP development as sponsors adapt to the new regulation, with prospects of more TEP market authorization applications in the future. Impact Statement Tissue-engineered products (TEPs) consist of engineered cells or tissues produced to regenerate, repair, or replace a dysfunctional, diseased, or absent human tissue. This article evaluates the regulatory landscape of TEPs and identifies the trends in clinical trial activity in the European Union (EU) since the introduction of Regulation (EC) No 1394/2007. This article identifies trends in TEP development, highlighting the most active member states, commercial involvement, a shift toward the use of allogeneic cells and a renewed interest in TEP development in recent years.