Apples and oranges. TheraSphere is targeted towards late stage cancer life extension. Radiogel is targeted for early stage 1 cancers. Of course FDA will hold an early cancer treatment like Radiogel to a much higher standard regarding collateral damage vs. a late stage treatment.
In any case, FDA flagged this months ago reviewing 2nd draft IDE that MK took over a year to submit. And now RDGL doesn't even have a path forward yet because of MK's gross incompetence and continued IsoPet distractions.