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05/04/22
19:22
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Originally posted by JB1975:
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Nope. Well perhaps you and I have different standards for what constitutes mere evidence as opposed to proof. To me if a plausible explanation for known facts is offered even if it is not the only plausible explanation then I'm willing to concede it could be evidence or even on first impression that yes it is evidence that I am being offered even if it doesn't rise to the standard of being conclusive or of constituting proof. Where was the evidence that it had different invivo or invitro activity compared to the previous manufactured product? In section 5.4 Remestemcel-L Potency and Efficacy Results on pages 108 and 109 is material I am personally currently willing to concede is evidence though I make no claim that it is proof. I won't type all the words from the pages out as I presume you can find and read them but I refer you to Table 41: Remestemcel-L Potency Assay Results for Product Lots Used in Sr-aGVHD and show you that for each of the three rows of items (from different manufacturing time frames) in the development program the levels of TNFR1 measured in picograms per millilitre and the level of IL-2Ralpha expressed as a percentage inhibition increase together. Protocol 280 which data is offered representing 163 patients had on average a certain amount of TNFR1 (tumor necrosis factor receptor 1 measured in picograms it seems) per millilitre and a certain percentage inhibition on average of Interleukin 2 receptor alpha was also determined. And Protocol 280 is "the previous manufactured product". Now in vitro is in glass or in a petri dish or in some sort of batch container so those averages of both sets of three numbers relating to TNFR1 and IL-2Ralpha would have been produced from measurements taken in vitro. They are in vitro measurements. There is therefor a clear trend. As the amount of TNFR1 goes up (on average - we are talking averages here) so does the amount of IL-2Ralpa inhibition. One doesn't have to be a scientist or a statistician to see that there is in fact a trend in the two sets of three numbers (205.7 < 241.3 < 321.8 and then in the other set 65.1 < 68.7 < 81,3). The simple trend of the numbers is something not nothing. Next look at Table 42: Remestemcel-L Potency and clinical Outcomes in Sr-aGVHD Protocols. Columns 1, 2 and 3 are just the same data as in columns 1, 2 and 4 from Table 41 but next to them are three columns of measurement of how the products from the different time periods (rows 1, 2 and 3) produced clinically meaningful outcomes such as day 28 overall response, Day 100 overall survival and day 180 overall survival. Again in all cases the numbers trend in together in that as the (alleged) potency and (alleged) activity quality attribute rise in absolute amounts so to do the outcomes measured. Now those samples are small but those trends in the numbers in the correct way are not nothing. That I submit to you Whytee is evidence even if it is not conclusive evidence. Were the trends in the numbers in the two tables to be different say declining against each other when they should be rising in unison - then they'd be evidence to the contrary. Evidence is still evidence. A trend even a simple trend is not nothing. Where were the potency assays to show a difference? In section 5.1 Critical Quality Attributes (which starts on page 24) there is a CMC Table 5: Drug Product Release Testing that has the potency and activity quality attributes. TNFR1 expression is the testing parameter for potency (its the first one of three, cell viability and cell concentration are others) and for the quality attribute of activity there is the testing parameter of inhibition of IL-2Ralpha expression. So that is the introduction to TNFR1 and IL-2Ralpha in a sense. Then at page 28 there is a table CMC Figure 13: TNFR1 Expression and T cell inhibitory function from donor number 3 in Study GVHD001/002 with two parts an upper part and a lower part to the same graphic each showing 10 separate lots. Now both the % inhibition and the TNFR1 sections of the graphic are on the Y axis and they are based at zero so its possible to see how much variation there is in picograms per millilitre terms across 10 lots (they all see to be between about 270 pg/ml and 355 pg/ml - so they aren't varying wildly 270 is about 76 percent of 355 - so it seems we are being show that if you have lots from the same donor the process can produce a range of TNFR1 which is about that range of consistent. Ditto for % inhibition. Now I understand that a single donor's lot results being sort of the same across 10 lots doesn't prove that other donors or also be as tightly clustered across 10 lots but I do understand that if you were testing each lot for minimum levels you should be able to do that. My point this doesn't show proof - I'm not saying the FDA is wrong - I'm saying that this is some evidence. In my opinion. Without them the claims are meaningless. I think you are too harsh in that conclusion. I think meaningless is too strong. I am not the FDA nor Mesoblast and you are not the FDA or Mesoblast but both of us are people that can look at material that is provided in the public domain and check it for consistency and where we see consistency rather than inconsistency I think we can credit at least that.
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Thanks JB, I just went over the FDA ODAC meeting again over the weekend. MSB and Dr Kurtzberg and the patients presented such a compelling case that we got 9:1 for efficacy. All other drugs for SR-GVHD also got approval without doing a randomized control trial. It's really one A*Hole from the CMC panel didn't like all the evidence. However, he did suggests that we Knock-down TNFR1 and see if the ability to down-regulate IL2R expression is reduced. I hope that MSB did this experiment, at least in vitro and look at its ability to inhibit PBMC activation . Because everything else that MSB has shown (as stated above by @JB1975 ) is correlation only. I call the CMC scientist an A*Hole because 1) the MOA of a lot of drugs are not known, worst FDA approved Aduhelm, which showed disconnect between drug and MOA. 2) that A*hole is not a clinician, so he wants to give very sick kids inferior products (products with lower vs higher level of TNFR1) and see if those received lower TNFR1 receptors died 3) The A*hole forgot that this is salvage therapy + on-top of standard of care (a salvage therapy means that nothing else works, otherwise it would have been used). I hope that triple A*hole clear his sh!T all at once (number 3) and stop blocking a salvage therapy that save kids' lives. It's only ~200 patients per year and MSB is happy to do a phase 3 on adult.