From what I read the really sad thing is how many of these failures are even not failure of the method or the underlying idea being wrong but pretty mundane things like failing to get funding for follow-up research, workgroups disbanding, PhD students finally throwing in the towel, researchers getting out of research for other reasons (family, ...).
My undergrad students did a research paper on this about 10 years ago (when I was a professor). It turns out that most promising results don’t get followed through for non-scientific reasons, mostly a lack of money. We never published the work (I left academia shortly afterwards), but it certainly was depressing.
I do realise the irony of not publishing this work.
I was going to ask for a link to the paper ... In particular "mostly lack of money" may mean "the results are not convincing enough to get more funds".
In this case they already tried something similar in mice, and they made a small business around the hat, and this is a preliminary safety trial, so I expect that they have a follow up.
For me, the results are not very convincing:
* They don't have a control group (because it is a safety trial)
* They have some improvements in difficult to compare test like the amount of words that the person can remember (it's standardized, but I guess you improve automatically the second time you try it, it's difficult to be sure without a control group)
* The blood sample test have a few changes marked as "significant" but they are using a very loose criteria to classify it as significant. The error bars overlap too much with the baseline.
So I don't expect that they get good results in a big double blind trial, but negative results are difficult to publish in journals and they almost never get press coverage.
Also (in other branches of science) it's standard to have a pipeline of papers. While one paper is published, other is been written and other is in the research part, and there are some brainstorming about what to do next. Once a group has a vein of subjects to publish about, it's much easier to continue with something similar.
Really? I doubt it. Sure, changing teams and funding may have a short term effect, but given how world-changing all the "miracle cures" that are announced would be, and that they so rarely pan out, makes me believe nearly all of these exciting breakthroughs have something fundamentally wrong.
