The key point to note is that is usual with in vitro brilacidin tests an inoculum was used.
That is to say brilacidin was already present when the potential pathogen was introduced.
The implication of this is that if brilacidin were to be employed clinically it would have to be administered prophylactically, that is before exposure to the pathogen had occurred.
It’s probably a tad impractical to administer IV brilacidin requiring an in-patient procedure to a healthy population as a precautionary measure, especially as well over 70% of those receiving it would experience either hypertensive spikes or peripheral neuropathy. Or both.
On the other hand brilacidin is useful to add to the publication list of post-grads eager to curry favor with their supervisor.