What happens when a medical treatment is no longer a standardised product, but is created for an individual patient — using living cells, biomaterials and a 3D printer, directly in the operating room?
This is one of the key questions explored by our team in the Report on key regulatory requirements for materials and processes.
Within STRONG-UR, we are investigating an ambitious regenerative medicine approach for the treatment of male urethral strictures. The concept combines a patient’s own cells with a hydrogel-based bioink and uses a handheld bioprinter to create a personalised tissue construct during surgery. It represents a shift towards patient-specific, on-demand tissue engineering, however, this innovation also brings a new level of regulatory complexity.
Report on key regulatory requirements for materials and processes
When existing rules meet a new technology
3D bioprinting sits at the intersection of several regulatory environments. Depending on the product and its components, regulatory requirements may involve medical devices, Advanced Therapy Medicinal Products (ATMPs), combination products, Good Manufacturing Practice (GMP) and Chemistry, Manufacturing and Controls (CMC) requirements.
Our challenge is particularly significant because the STRONG-UR approach brings together living cells, a hydrogel bioink and a specialised bioprinting device. Determining the appropriate regulatory classification, defining responsibilities and demonstrating the safety and reproducibility of an in-situ manufacturing process are far from straightforward.
The report also highlights an important reality: 3D printed implants are not automatically considered custom-made devices under the EU Medical Device Regulation (MDR). At the same time, current legislation provides limited guidance for bioprinting workflows involving living cells, novel biomaterials and decentralised production.
Quality cannot stop at the final product
For bioprinting, regulatory compliance is not simply about testing the finished construct. Quality must be built into the entire manufacturing process.
The report examines requirements ranging from raw material qualification and traceability to bioink characterisation, sterility, process control, equipment qualification, software and digital workflows, and process validation. Critical process parameters need to be identified and controlled because they can directly affect the critical quality attributes of the final construct.
This becomes particularly challenging when every construct may be different and conventional destructive testing may not be practical for a patient-specific product. At the same time, many established sterilisation approaches may be incompatible with sensitive biomaterials and living cells.
Can regulation evolve with the technology?
Our team highlights the need for regulatory approaches that are better suited to personalised 3D bioprinting. A process-based approach, focused on ensuring safe, controlled and reproducible manufacturing, could offer a promising way forward. For STRONG-UR, point-of-care manufacturing is currently considered the most plausible pathway, while important questions around regulatory responsibility remain. The report identifies these challenges and proposes practical considerations to support the clinical translation of the STRONG-UR approach.
The report provides a valuable roadmap for understanding where regulation meets the rapidly evolving world of 3D bioprinting. It brings together the current regulatory landscape, GMP and CMC considerations, relevant international standards and guidelines, specific challenges for bioprinted products, and practical considerations for STRONG-UR’s regulatory strategy. The future of personalised regenerative medicine will depend not only on what we can print, but on our ability to demonstrate that what we print is safe, consistent and clinically reliable.
