The Cords that Bind
A quick guide to a cell therapy starting material that demands a little more attention: cord blood
Angus Stewart | | 4 min read | Interview
How much do you know about cord blood? Well, with years of academic and industry experience and the job title of Director of Product Management for Be the Match BioTherapies, Joy Aho is well placed to get you up to speed on the ins and outs of handling this special cell therapy starting material.
Could you please give us a brief tour of typical starting materials for cell therapies?
First, I should emphasize that cellular starting material is a critical – if not the most critical – component in cell therapy manufacturing. And, therefore, it is important to consider many factors when making decisions around cellular starting materials, including the source. There are widely varying biological differences between different starting materials, which, in the cell and gene therapy industry, largely include adult non-mobilized apheresis material, mobilized apheresis material, and cord blood. Understanding these differences and how they can impact the safety, efficacy, and scalability of your therapy are critical. You also need to be aware of any particular critical quality attributes associated with that material once you make a source decision – and you will need to pay careful attention to how these may impact scalability as you progress through clinical and commercial phases.
What’s special about cord blood?
Cord blood – a mixture of blood cells derived from umbilical cords – contains an interesting combination of cell types, one of which is the hematopoietic stem cell, which is capable of generating any cell within the immune system. As cord blood is generated at the time of birth, the cells are more naïve and have had less exposure to environmental agents that may cause mutations. These properties can be advantageous to many therapy types, most notably the generation of induced pluripotent stem cells that may be leveraged for the development of a variety of therapies. Additionally, cord blood has a higher percentage of natural killer (NK) cells which may be advantageous to the development of novel NK cell therapies. Cord blood is readily available, cryopreserved, in banks across the world. Adult donor apheresis material is the more common starting material alternative to cord blood, which has its own advantages, including the potential for more extensive upfront screening, the volume of cells, and the capacity to obtain repeat donations from the same donor.
Are there any special supply or ethical considerations for cord blood?
There is a misconception in the field that it is very difficult to obtain cord blood units for use in both research and the clinic. In fact, cord blood banks want to make sure that this very valuable resource can be used in the development of new treatments. There is a large inventory of these units available – and processes for obtaining these units tend to be simple and straightforward.
Of course, it is always important to ensure that ethical issues are taken into account for any donated tissue. Just as with adult donor material, it is critical to ensure that the donating party – in this case the mother – is fully informed and knows what the cells may be used for. Consent language has evolved over time to include a comprehensive list of use cases, including commercial development – and procedures are in place to ensure that mothers are under no pressure to donate. Notably, the language and process are reviewed by Institutional Review Boards, whose focus is on the protection of the rights of human subjects.
Have practices for cord blood supply changed much since their inception?
Cord blood banking practices have evolved over time, but there has been considerable consistency in practices – especially since 2011, when the FDA first started to grant Biological License Applications for the use of cord blood in transplants for several hematological indications.
In terms of evolving in the future, especially in the context of emerging cell and gene therapies, there could be modifications in terms of how cord blood is processed, cryopreserved, and tested to help support emerging therapies. In this area, multi-party organizations like the Cord Blood Bank Alliance are already working with developers to understand common needs across the industry, with a view to updating and adjusting current practices.
How do differences in regulations around the world play out in the use of cord blood for cell therapies?
There are definite differences across the globe in terms of regulations around starting material – many of them relate to the type of testing demanded of that material to ensure safety for the patient. Infectious disease marker testing is a great example of where variations, based on disease agents endemic to particular regions, exist across geographies. The type of testing and appropriate specimen type (samples from the mother versus the cord blood) may also vary. There is a great need for clear guidance from regulatory authorities on cord blood testing requirements for use in emerging therapies, and how this may require evolution of current banking practices.