In our recent webinar titled “PK-PD in support of accelerated programmes for antimicrobial development: how much is enough?” with William Hope, we received more questions from the audience than we could answer during the session. We will now follow up on some remaining questions in the forum and encourage our experts but also users to discuss these questions.
The critical question is what are the levels at the site of infection. For example if PK is determined in blood, but the intended target is the lung, and there is no correlation between the levels in blood and levels in lung, the levels in blood become irrelevant. Route of administration is also a very important parameter, if the intended route of administration is oral and all the PK determinations are done IV, those levels will not be very meaningful unless your drug is 100% bioavailable or you have good information about the correlation of oral vs IV levels. Also you need to keep in mind that the toxicity profile can differ depending on the route of administration.