I remember reading about this---thought it was in Scientific American recently, but I'm not sure. It sounds gross, but it makes a lot of sense to me. Read more at this Wikipedia page http://en.wikipedia.org/wiki/Helminthic_therapy#Research
They choose whipworm and hookworm species that are not native to human intestinal tract, so there is little danger of infestation or spread.
I like to keep an open mind about these things. Although disgusting-sounding, the side-effects are definitely not as dangerous as some of the strong drugs available for treating autoimmune diseases. I have not read anything about this therapy being used for Sjogren's, but for Chrohn's, ulcerative colitis it seems to work.
It does have a scientific basis, and is surely an alternative to expensive drugs pushed by pharmaceutical companies. I wouldn't think that Big Pharma would touch this with a ten foot pole. Other researchers, however, sound like they are motivated by finding answers and relief for patients---not just profit.