2 comments on “New Dementia Trial Results

  1. Annovis stock dropped last month after they presented more data.

    Their reported 30% improvement in cognition is less impressive than it looks, because there’s apparently a nontrivial placebo effect. The group that got the placebo showed an 8% improvement in the same measure of cognition. That’s almost certainly related to limits on how well cognitive changes can be measured, rather than actual health improvement.

    It still looks like the treatment caused a real improvement, but the trial was too small and short to inspire much confidence.

    I bought a few shares in Annovis in early summer, and a few more after that big decline.

    Cassava shares dropped last week after a lawyer petitioned the FDA to stop Cassava’s simufilam trials. The lawyer’s knowledge of biology seems questionable. E.g. he claims:

    It is unlikely that the enzyme responsible for phosphorylation would survive the initial -80°C freezing step. Moreover, the phosphorylation experiments are reported to have been performed at 4°C, but it is unlikely that the enzyme responsible for phosphorylation would be active at 4°C (enzymes generally work best at body temperature—37°C).

    Whereas I’m pretty sure that enzymes usually survive freezing, and are usually active at 4°C (albeit slower).

    I see only one point on which Cassava seems to have done something suspicious: figure 5 of this presentation shows one patient having an increase in P-tau181 levels that looks to me to be a bit over 100%. The lawyer says it shows +235%, and Cassava says it was 38%. It sure looks like Cassava did something incompetent with that figure. I guess that’s slightly more likely to happen if Cassava was faking data than if Cassava was honest, but one data point doesn’t tell me much.

    It’s pretty normal for a law firm that specializes in class action suits on behalf of shareholders to make frivolous claims, which markets usually ignore. But there’s massive uncertainty about how much Alzheimer’s drug companies are worth, so it doesn’t take much to cause big fluctuations in price.

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