Bruce P. on twitter has no idea why the FDA gave R

Bruce P. on twitter has no idea why the FDA gave RTF for HIV combo BLA. He is guessing. I'm also not sure what he says is accurate, that Nader blamed InCellDx for the RO assay as the reason for the BLA RTF. As Bruce stated, InCellDx didn't do any RO assays for combo trials.

Regarding Citron, what can one say about someone who twists the truth?

For instance, the paper he linked in SA says the following about RO testing:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2311409/

Quote:

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Conclusions

Maraviroc receptor occupancy close to the maximum is required to induce a significant decrease in viral load, indicating that in vivo CCR5 receptor occupancy by maraviroc is not a direct measure of drug inhibitory activity. Considering the imprecision of the measurement in the upper flat part of the maraviroc concentration vs. percent CCR5 occupancy curve, it can reasonably be concluded that routine monitoring of receptor occupancy as a biomarker for maraviroc efficacy will not be helpful. Based on this analysis, it was decided not to use receptor occupancy as a biomarker of viral load inhibition during the development of CCR5 antagonist compounds.

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It says that routine RO monitoring would not be helpful, based on Figure 2.

I'm not sure why everyone is clamoring for more RO monitoring, other than InCellDx, which makes a test kit to do so. It might be helpful in HIV, Covid, and other indications, but I have yet to be convinced.

It sure looked to me (from memory of Montefiore Covid data) like everyone gets to 100% occupancy by day 14 after 700 mg dose of LL on days 1 and 7. Almost all get to 80% by day 7, from the data I've seen.

Would more frequent monitoring of RO really be necessary or helpful?

Regardless, I guess we need to prove to FDA that high CCR5 RO is achieved for combo HIV therapy, for some reason, and that may take some time.