I don't think the FDA wants to be 'told'. Remember, they are the ones to whom one has to 'demonstrate', and they are the final arbiters of whether it's been demonstrated.
But I think - under various pressures - theyre getting round to doing the right thing anyway. In the fullness of time, as Sir Humphrey might say. From here it feels like glacial slowness.
Here's some numbers you might find interesting, in a light-hearted way. Out of only 34 cell and/or gene therapies approved by the FDA as at 26 Dec 2023:
A. 26 ex 34 were cellular therapies (so pure gene therapies are still in the minority, but the FDA might reasonably think it has a better handle on cell therapies)
B. 13 ex 26 were autologous cell therapies (which goes to my point about the FDA being comfortable about autologous anything - because if its bad, its all on you)
C. 8 ex 13 were allogeneic haematopoietic cell therapies ( which goes to my point about the FDA being comfortable that they understand blood, even if its someone elses blood. They can match it, right? - Bob's your uncle. Or, more accurately, the FDA think someone can prove he's your uncle.)
D. 5 ex 13 were allogeneic cell therapies - i.e. the rump, but ALL of them were from or differentiated to keratinocytes or fibroblasts or pancreatic islet cells i.e. mostly inert scaffolding.
E. 0 ex 34 were allogeneic non-haematopoietic cell therapies. [ THIS SPACE RESERVED FOR MESOBLAST LTD IN 2024 ]
I think anyone looking from 30,000 feet can see how, looking at CGT therapies, and specifically cellular therapies, and then on down into haematopoietic cellular therapies, and then even more specifically haematopoietic tissues (HCT/Ps) which are introduced autologously during oncological treatments (HSCT), and then with even greater specificity haematopoietic tissues (HCT/Ps) transplanted allogeneically into other humans during oncoligical treatments (HSCT) the FDA reviewers might think they now had a handle on all the perturbations of MOA etc of these pesky cells.
But they don't, just from what's gone before - because allogeneic non-haematopoietic tissues behave differently. They're not trying to become part of someone else's body. Just do their job and get out. No coffee and they didn't even park in your driveway.
It's about time that the FDA stopped jumping at shadows, and thanked the golden goose (that's us).
But they won't. I'll settle for an accelerated approval.
(20min delay)