The above means that at least 4 subjects out of 13 in the starting IGA 3 group must have improved to clear/almost clear groups (IGA 0/1) in the end.
No, the company stated that 6/13 from IGA 3 group (200 mg PP) went to 0 or 1, that's how they get the 46.2% in their PR.
At the end there is still 20 subjects but distributed now: 3 in IGA 0, 8 in IGA 1, 3 in IGA 2 and 6 in IGA 3
We know that only 1/7 (since total was 7/20) in original IGA2 group went to 0. So that means the other 2 in final IGA0 were from IGA3 group. That means 4 of the final IGA1 were from original IGA3, and then 4 remaining final IGA1 were from original IGA2 group.
So, here's how it went down in the 200 mg PP group:
13 IGA3: 2->IGA0, 4->IGA1, guess: 1->IGA2, and 6 stayed at IGA3 7 IGA2: 1->IGA0, 4->IGA1, guess: 2 stayed at IGA2
Feel free to make whatever inferences you want from it, but that is the data from Prurisol Phase 2A at 200 mg PP group.