It is immunosuppresive. Basically they say it is good for preventing,or slowing down old age cancer so you live longer. The trade off is that becaue it supppresses the immune system your risk of infections can increase.
It is interesting but needs more research. If you can stay infection free or dont have big allergy problems it may be a good thing.
Although the dogs in this study received a non-immunosuppressive dose and the drug had an effect in a matter of days or weeks so something else is going on. Wish there was more funding for clinical trials in healthy human adults. If more of these animal studies turn out well people are going to start taking it regardless of FDA approval.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5411365/