Have you looked into biomedical treatments? Many kids with ASD benefit from MB-12 injection. It sounds scary but we've been giving them for 6 months now. It's 0.05ML which is a TINY dose. You can read more about it at www.drneubrander.com
He also has video studies from kids he had no speech or had echolalia who started speaking within 2 days. My son isn't "talking" but he did start syllobals when we started MB-12. He just doesn't have his constanants down. It's really helping him though.

Also the GFCF diet is very beneficial for many ASD kids.

Good luck! Here are a couple of websites.
www.generationrescue.org
www.tacanow.com
www.danasview.net

-Crystal
www.sashasrecovery.com