banter and General Discussion, page-11422

Thanks OP.

2 things from reading JayB’s long posts, that I should clarify once more. I have done both before, but not sure if it registered.

As is clear from the below draft FDA guidance published in late September 2023 on potency tests for cell and gene therapy products, it’s the drug developer or sponsor’s job, not that of the FDA, to demonstrate the validity of the potency assay test(s) - see p.14 of https://www.fda.gov/files/vaccines,%20blood%20%26%20biologics/published/Final-Guidance-for-Industry--Potency-Tests-for-Cellular-and-Gene-Therapy-Products.pdf

This is fundamental. JayB has talked over and over about the FDA having to validate the company’s tests. It is not true. There is a clear distinction between what he said and what is required.

Secondly, anyone harping about the FDA’s concern about the lack of a 2-arm clinical trial (I note that JayB has underlined “2-arm trial”) should look at the timing of this draft guidance on GVHD treatments that was published also by the FDA in late September 2023, as it represents the FDA’s most up to date position. Note that it was published shortly after the Type A meeting with the company. The 2 may or may not be directly related but it provides clear confirmation that neither is it a current “concern” of the FDA’s, nor is it still one, if it ever was before the Type A meeting last year.

In the latter case, if the discussion in the said meeting in fact prompted the clarification in the published guidance, then it means that the FDA might have been convinced that it should not be a concern if it had previously believed that it was. (This was the meeting where people from the prestigious BMT-CTN were present to talk about the proposed trial in adults. This adult trial is now either going to be a label extension trial upon full approval for kids, or confirmatory trial upon conditional approval for kids. We learnt recently about post-approval commitments that the option to issue convertible notes should help to cover (we know the BMT-CTN will largely but not fully fund that trial).

Refer to p.19 of this below draft FDA guidance specifically on GVHD, again published in Sep 2023, on how the FDA clearly states that aGVHD results may be accepted from single arm trials where patients are refractory and there are no available therapies - both of which conditions are satisfied by the company’s Phase 3 trial on steroid refractory kids with aGVHD.

https://www.fda.gov/media/172524/download