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Gut check: Seres Therapeutics shares plunge after microbiome drug fails in trial

Made stock market news. Disappointing to see.



...In a phase 2 study, SER-109 did not reduce the risks associated with the infection, compared to the placebo, at up to eight weeks of treatment.

Seres Chairman and CEO Roger Pomerantz said, in a press release, that the clinical results were "unexpected" in view of positive data in prior investigations and supporting clinical data.

"Specifically, the recurrence rates observed in the overall SER-109 treatment group, in the age stratified subgroups, and in the placebo groups are inconsistent with our expectations," he said. "Our priority is to complete a full review of the clinical results and microbiome data of the phase 2 study and to compare it to data from the prior investigator sponsored Phase 1b."

Seres said it will continue to gather and analyze study data, and in consultation with the U.S. Food and Drug Administration, make appropriate adjustments to its SER-109 development plans.

However, investors saw the results as potentially warning about the entire area of microbiome therapeutics, which has been looked on with much promise. The burgeoning field looks to treat illnesses by adding "good" bacteria to your digestive tract.

Seres is one of several companies racing to do that. Others include Vedanta Biosciences, Enterome, Second Genome, EpiBiome and uBiome.

The spokesman for Seres didn't immediately respond for CNBC's request for comment.
so supposedly these pills by seres ser-109 only had 100million spores in it. that sounds like nothing to me because first of all there are only 50 types of bacterial spores in these pills when there are 1000 different species of bacteria in the gi tract and 7000 different strains and 10 trillion total bacteria. considering these people are sick and these are spores not live bacteria, I kind of expected that trial to fail. but I really don't know much about spores other then they are in a dormant state which wake up when the environment to grow is hospitable to them, is a sick person gut hospitable to spores? probably not, you'll likely need a high amount to over power the disease process which enables the bad to persist more then the good. But i would think they at least tried their pills in mouse models of colitis to get an idea of what dose would be good for humans but still to me it seems too low of a dose assuming the bacterial strains they have chosen are effective at all in the first place. they will get it right eventually many more companies on path to do the same thing.

I do believe that this can be done with a small group of bacteria, but it seem like a time consuming process to explore when we can use whole stool right now. But in a way this is also a failure in scientific reductionism and there may not be a one size fits all for every patient, at least not exactly as precise as they want it to be.
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I read some more about this trial, in the interest of trying to figure out if I should buy some Seres stock, since it's on sale for such a nice discount right now.

What I learned is that they had a large number of 65 and older subjects in the Phase II trial that had had at least 3 different C. Diff infections over the past year. They selected this population group because they are typically harder group on which to perform colonoscopies, which is the most effective way of delivering FMT for CDI, and so a good segment for which the pill form would be beneficial. This group may have overwhelmed the results.

Additional data will be released in about 16 weeks. And they are also working on synthetic, more potent forms that will also be trialed soon.
Hahaha, well I'll be passing on the synthetic if it comes out.

Been having some luck with an idea avoiding synthetic vitamins directly and indirectly of late. With a little luck the idea will continue to work.

I haven't looked it up, but I've wondered if the oxygen ozone treatment would work on C-diff. I've read that ozone is good at killing off unwanted bacteria and fungus. Apparently someone wrote that good bacteria do not mind oxygen and bad have a difficult time surviving with it. At least I have that in my mind for some reason. I'll have to look that up sometime.

Good luck with the stock buying.
I buy stocks that are bad news stocks. If the company has other stable drugs already approved, they can be over sold on news like this. I recently bought VRX for the same reason.

Haven't looked into this one as I am heavy on pharma already, so do your research first.

Too bad the results were so unremarkable. Perhaps the delivery method needs more work. Prebiotics may help the outcome also.