The inclusion criteria for part 3 was patients with high grade serous ovarian cancer which is very metastatic often diagnosed when the cancer has already spread to outside ovaries. The CR by definition is disappearance of all target lesions.
As for PR again the definition is at least 30 percent reduction...
Would the one patient with a complete resolution of a liver lesion be classified as a CR as the targeted cancer was ovarian cancer?
The more than 25 percent shrinkage of the tumour size seems to be just short of being classified as PR, It almost seems like they need to reveal more details so one can get better understanding of the results for instance which tumours had 25 percent shrinkage? What was the plasma concentration of free docetaxel?
Overall as it was mentioned those results are from a small number of patients that's why one can be optimistic about the outcome plus they seem to be more confident about further dose escalation with these shortened dosing intervals due to a better safety profile of the drug this time round.
Now my guess is that they need to find that partner moving on with part 4 most likely as the RP2D was not mentioned in the PR and they are now talking about higher doses to find the MTD. Also I have the feeling that they haven't released all details yet. I think these results plus all the various previous data should be good enough for further research/ allocation of resources. Note the participants have been heavily treated, up to 8 prior cancer treatment regimens!!