We tried Vyvanse when my oldest was 7 years old. From what I recall, (he’s 17 now) it didn’t seem to have any noticeable effect on his hyperactivity or his focus. From research though I did discover that meds are not tested on children under 7, thought this is worth mentioning. It really is lots of trial & error to find what works for each individual child.
I’ve heard Guanfacine works well for many ASD kids, but it made my son extremely groggy & emotional.

I hope you find one that works well for your son.

I'm not familiar with that medicine. Really it takes a lot of trial and error. My oldest son was on methylphenidate. Later on we needed to address his aggressive behavior, so our pediatrician added guafacine. Well, we had trouble getting the methylphenidate and he was off it for a few weeks. He was still on the guafacine. We found out the methylphenidate was making him aggressive.

He has done so much better on the guafacine. He needs it two times a day but I feel like his personality isn't subdued liked when he was on the methylphenidate. I hope you find something that works!