I understand how this could be overlooked or confused as the PR headline itself states that the poster was based on "in vitro" testing of Brilacidin but my post was referring to the actual Poster Presentation that can be found in a link from the PR. It is stated on the Poster Presentation under the heading Discussion/Conclusion. In the last sentence it states: "Ongoing efforts are focused on dosing strategies for brilacidin to improve in vivo effectiveness in the form of a nasally-delivered countermeasure."

Latin lesson for the day: Studies that are in vivo (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and plants, as opposed to a tissue extract or dead organism. This is not to be confused with experiments done in vitro ("within the glass" i.e.,in a laboratory environment using test tubes, Petri dishes, etc.