Countless ATMP facilities have been inspected resulting in several re-occurring issues (see Table 1). Many findings have led to new guidances and improved facility designs enabling robust process designs and lowering contamination risks. Despite these improvements, inspection findings in ATMP facilities remain high.

From a regulatory observation, upgrading a clinical trial drug product manufacturing site to commercial manufacturing can be a daunting task. For example, a facility design may be ill-suited for a process commercial production campaign, the procedures may be too general or unspecific, and the staff may have the habit of prioritizing yields (a process development goal) over process controlling aspects of manufacturing. Historically, many ATMP manufacturing sites emerge from multipurpose facilities such as university hospitals or clinical trial phase I production facilities. These facilities required a high degree of manufacturing flexibility, as they were designed for clinical supply, and thus introduced a degree of academic or sometimes hospital (exemption) rules into the cGMP playbook. The more established players – apart from having larger budgets – build facilities where the process defines the product and they may encounter fewer facility risks, along with a reduced need to retrain staff to break habits.