Regulating an individualized therapy by validating its fixed manufacturing process and platform, rather than the final molecule — which differs for every patient.
When the product can't be held constant, the regulator's answer is to hold the process constant: validate and lock the manufacturing steps and release specifications, and treat that validated process as the thing being approved. Industry shorthand calls this "the process is the product." The FDA already runs autologous cell therapies (CAR-T) this way.
The FDA's draft Platform Technology Designation Program (2024) gives this a formal vehicle, letting a sponsor carry prior manufacturing data forward as "prior knowledge" for each new product built on the same platform — and it explicitly names mRNA/lipid-nanoparticle systems. It is the lever an individualized-vaccine maker needs, but remains draft guidance, untested for a marketed product.