In the total the FDA has held 3 days of public meetings on stem cells in the last few weeks ranging from science to policy and hearing from many parties including patients and even stem cell clinics so the big question now is, “what happens next?”
The FDA has 4 draft guidances pertaining to investigational stem cell clinical procedures and these were the subject of the second meeting that last a couple of days. Soon the FDA’s online commenting period related to these issues will close (you can still make comments here, but don’t expect the comment to appear quickly as I submitted mine 4-5 days ago and it’s still not up).
Once that is done, can we expect the FDA to finalize those guidances? And if it does, will the guidances change at all due to the meetings or online comments on the docket? My sense is that the FDA will take at a minimum months to consider the comments at the meeting and those submitted online so it’ll be 2017 most likely before they are even close to taking a next step at all.
I do not expect the guidances to change substantially. As a stem cell biologist, I didn’t hear anything at the meetings in terms of science or data that provided a compelling rationale to change the guidances. The FDA should base its decisions on the biomedical science.
There were a variety of ideas presented at the meeting for changes or new elements to the stem cell clinical arena including a “middle ground” that would get stem cell therapies to patients more quickly, but the trade-off there is that there would be far less data to support the potential safety and effectiveness of those stem cell products. On the whole this would simply put more patients at risk in my view.
Several speakers mentioned starting a registry for stem cell clinics, but I don’t see that as having a major positive impact as there are too many unknowns and complexities. Who would run the registry and pay for it? Who would oversee it (the FDA?) and what would happen if commercial entities were noncompliant with participating in the registry? What about the already existing clinicaltrials.gov?
A big meme at the FDA meeting was the idea of very widespread functional homology of fat stem cells throughout the body via paracrine signaling. Yes, the heterogeneous cells within “fat stem cell” products do make many growth factors that could act in a paracrine manner, but I don’t buy the idea that this makes them homologous to many diverse tissues in the body and I don’t expect the FDA will either.
The FDA could never finalize the guidances, resulting in either the status quo continuing of thorough oversight of the good citizens of the field and little-to-no action on the stem cell clinics. Or even without finalizing the guidances, the FDA could step up its oversight of stem cell clinics, which would be helpful given that there are around 600 of them in the U.S. operating without FDA approval and the FDA has been issuing <=1 warning letter per year lately.
If the guidances remain (finalized or not) and are the basis for the FDA’s current thinking moving forward, then most adipose stem cell clinics should be subject to FDA action given that they are using more than minimally manipulated cells and hence drugs in an unapproved manner and they are almost always using the cells in a non-homologous manner.
Perhaps in the short run the most likely thing is that nothing will happen. As my state’s governor Jerry Brown once famously said to voters, “lower your expectations” and perhaps that can be applied to the FDA on stem cells. However, I’m not going to do it. I’m going to keep my expectations high on this.