MTD and the FDAScarlett brought this news to the board about the fda seeking alternatives to MTD.
https://www.fiercebiotech.com/biotech/fda-s-renewed-focus-oncology-dosing-spooks-investors-but-companies-say-they-were-ready It got me thinking about how thtx might handle this (if they had to), I'm not suggesting they have to atm. Anyway it's pretty well known how normal docetaxel accumulates in tumours. You can use that concentration as your target concentration for dosing. So rather than rely on MTD to find the maximum dose based on safety you use a tumour accumulation number to get a dose based on efficacy. You can only do this because you have the long experience of using docetaxel in patients. I'm not saying this is what they'll do, to me it's just another example of how it might help the drug development process to be using an old, well-understood chemo.
Hopefully they get tumour material and are able to measure drug (and released docetaxel) in the tumour. It will be a good number to have for many reasons. If investors were truly spooked by the FDA's shift from MTD, it would be good for thtx to have a pre-prepared solution.