I don't know.
But I know that there are 150 folks in the Tovaxin phase IIb trial. Lyon would be a good person to ask about it. I know there are studies that are done with a dozen folks and I think the last Tovaxin trial was small like that. But, I don't think the big problem with trials is the number of people.
We live in a world of government regulation and for as much as we want to think or disbelieve that the government is protecting us, it does and doesn't in the oddest of ways. A great example is the current issues we read about lead paint used on toys made in China. Sounds simple, but actually the federal government has standards that do allow some toys that contain lead to go on sale without recall. My point is that the federal government is so thick with regulation that no human can possibly read that if you make one tiny error in how you do something, you get fined millions of dollars unless you've made a $1,000 campaign contribution to the one that wins the Whitehouse.
There's a lot of administration to gathering knowledge and backing it up and having the records to show that you did it correctly and met all the rules. We're coming up on the most personal of all interactions with the Fed - income tax time. Yup, isn't it a pain. Isn't it seemingly ridiculous to have to fill out those forms and some folks have to complete lots of them. And that don't include whether you get asked to prove that you filled them out right via an audit.
The government wants trials and trials are expensive to conduct because a lot of red tape has to be completed. This is why you'd better have a drug that maintains the illness so folks have to keep buying it. This is why drugs get made for illnesses of the many. This is why Viagra got made and most folks are still using needles for MS meds. This is why taking some pills that are available as generics isn't getting much attention. Yeah, Pfizer makes most of the antibiotics in the Wheldon protocol, but they also make Rebif - guess which makes them more money.