We've had my mother-in-law on IVIG for Alzheimers for the last three years, after initial reports on the treatment. We started during what I would consider the early mid-stage of the disease and, while one can never be sure, her doctor believes she has benefited. It is extremely expensive.
If Momenta is successful in developing a version which allows IVIG to be more widely available at reasonable prices, I have to believe it will be hugely profitable.