Replies to post #112925 on Biotech Values

[FreeNorth]

PYMX compounds kills bacteria in the same way that natural defensins do

I think this MoA will prohibit oral versions of these antibiotics: they kill bacteria too well. It is not a good idea to clear all the bacteria from the gut. That leaves, however, a large arena for use.

[iwfal]

multiple passes of less-than-lethal concentration have no effect on MIC, unlike any other known antibiotic.

I agree that the serial passage data is a first step in proving that you aren't inducing Armageddon. But then note that:

a) Serial passage data for some micro-organisms vs some anti-biotics looks a LOT better than others. And their drug's serial passage data is all staph-aureus. However if they tried the same test against the 100 most widely variant strains of microbes living around humans I'd bet 10,000:1 they'd find a few that didn't have that comforting flat curve. One good place to look would probably be the gut. And of course microbes swap spit every once in a while. Also note - there are bacteria with resistance to defensins.

b) I would guess that the serial passage data for an antibiotic introduced long ago generally looks a lot worse than when the drug was first released. Unless they are completely confident in their bacterial lines haven't picked up anything. So the comparison isn't entirely fair.

In toto I would still strongly suggest this is playing with fire - of the type on the surface of the sun. Maybe it's safe. But I sure wouldn't bet against mother nature - at least without one heck of a lot of data. Accordingly I'll bet another 10,000:1 that 20 years after this drug is introduced (and I surely hope it isn't) that resistance is cropping up.