https://news.ycombinator.com/item?id=44014862 has 26 comments.

Apologies for the double post. I got a "link expired" error when submitting so assumed the original post had not succeeded.

It appears that the trial is still ongoing: https://www.cancer.gov/research/participate/clinical-trials-...

The theory is that the taurine added to the drinks is feeding gut bacteria that then produce hydrogen sulfide that damages the intestinal lining.