Zachary's dr. at Johns Hopkins directed us to the below trial, but Zach has exluding factors and they won't accept him. If you live within a 3 hr drive of Bethesda MD, it may be something to consider. I believe you have to have monthly visits at the NIH.
www.clinicaltrials.gov/ct/show/NCT00409747?
Also, this is a list of all the autism trials ongoing, haven't looked closely, but it may be helpful for someone.
www.clinicaltrials.gov/ct/screen/BrowseAny?
Obviously we're too far away, but I just wanted to say thank you for posting this. I hope others see it and are able to participate.