FDA guidance on expanded access which would pertain to continuation of phase one first cohort:

http://humansubjects.stanford.edu/research/do...I01019.pdf

Evidence:
(i) When the expanded access use is for a serious disease or condition, there is sufficient clinical evidence of safety and effectiveness to support the expanded access use. Such evidence would ordinarily consist of data from phase 3 trials, but could consist of compelling data from completed phase 2 trials; or
(ii) When the expanded access use is for an immediately life-threatening disease or condition, the available scientific evidence, taken as a whole, provides a reasonable basis to conclude that the investigational drug may be effective for the expanded access use and would not expose patients to an unreasonable and significant risk of illness or injury. This evidence would ordinarily consist of clinical data from phase 3 or phase 2 trials, but could be based on more preliminary clinical evidence.

Obviously - kevetrin would fall under second paragraph and could base cohort continuation of lack of harm and possibility of positive effect ( "may be effective"). Per FDA, drug does not have to have proven efficacy for this kind of cohort continuation. I am a stickler for misinformation.

Best case scenario - the cohort continues because they have experienced measurable benefit! That would be our dreams come true!