Strange that they are using PEO and cyclodextrin as a "encapsulating" polymeric source for the transferrin. I would think that PEO would be not very good choice for living cells (cancerous or non-cancerous). If the body needs to digest this polymer, PEO has a history of problems with its by-products. Most of the by-products are ethanol, which would kill the cells. Probably callogen or similar forms would be better. Perhaps, they are already using similar types of polymers.