You don't want to see clinically significant lab abnormalities or that the drug has a clinically significant effect on vital signs, QTc or ECG parameters. You can see AE in a phase 1a trial like in the case of ANA598, where 3 of 24 subjects dosed with ANA598 discontinued therapy due to grade 2 rash in the a healthy volunteer study (it was a 14 day study though).
According to the PR, there were "no clinically significant changes in vital signs, ECGs, or laboratory evaluations." So, again, I think this is a case of "so far, so good" with the caveat that this study just went out to 5 days and that there's still a long way to go in the clinic.