Safety information is required to allow clinical development of stem cell products, but clearer guidance concerning safety testing requirements is still needed.
Stem cell products hold great promise for multiple clinical indications and are actively studied in clinical trials (1). However, many related safety features raise concerns and currently generate extensive and costly testing of the final product, if intended for clinical use. The regulatory expectations for stem cell testing for clinical studies, as well as marketing authorisation applications, are not entirely clear, up-to-date or detailed. Furthermore, differences between US and EU guidance, in this respect, hamper the current development
of products for EU markets.