IS / LGS Meds not working

Hello, Here is our backstory. My son was diagnosed with infantile spasms at 6 months, we went through alot of meds to get it under control. Started with ACTH, Sabril, Pheno, Onfi, Banzel, and a few more I can't remember off hand. Nothing seemed to work. We were having up to 200 seizures a day. We have progressed into LGS as he is now 2 1/2 years old, with the development of a 2 month old, he is also gtube fed due to too many seizures to safely eat. He is currently on Keppra, Omfi, Depakote sprinkles and the Keto diet. We feel the keto has been the most helpful dropped his seizures from 200 a day to about 25 a day. We have tried so many meds and nothing seems to work and we need help getting any information on CBD. We've been doing alot of research on CBS. We want to try it but don't know where to start. We don't know where to look up trials or how to talk our doctor onto it. Sorry is some of this makes little sense, hard to put the whole story out.