What I think needs to be factored into the near perfect safety record concept, is that patients are being titrated towards their respective assigned dose arm milligram levels of A2-73 (or placebo).
So although there clearly are no glaring safety issues, we don't know the distribution of actual achieved doses in each dose arm.
I remember seeing dizziness as a side effect of A2-73 in a previous clinical trial report...about a year ago. It noted that there weren't any more serious side effects than that. (and perhaps a little nausea). But nothing like headaches, vomiting etc.