First heard about "Fen-Ben" a couple of years ago. I am not a doctor, but I believe it's the real deal. No real side effects. The protocol can be used concurrently with standard treatment. A ketogenic diet and a supplement regimen are part of the protocol for maximum effect. Now Ivermectin can boost the effect too.
Joe Tippens seems to be the man who helped develop the "Fen-Ben" protocol. There is lots of info on the interwebs about it.
https://mycancerstory.rocks/