Hi and welcome to the forum!
It sounds as though you're really suffering with the UP. Maybe others here with it will have some ideas for you.
Midostaurin (also called PKC412) is still in clinical trials and not yet approved for use in indolent SM, as far as I know. I've spoken to a couple of people who've been on the drug for about 2 years, and they were approved because they have ASM. I'm sure Dr. Castells knows more about it than I do, but I don't know of anyone with ISM qualifying for the study.
There's an article online, published by Georgia Health Sciences University about Ralph Brown, one of the patients:
http://www.georgiahealth.edu/cancer/clinical/trials/brownstory.html You might be able to contact him through GHSU.
The closest site for a Midostaurin trial, I believe, is Stanford Cancer Center in Palo Alto, CA. Dr. Jason Gotlib, in the Hematology Dept. there, would be a person to contact about this. He's a great doctor, in my opinion.
There are a couple of notices on this forum about the Colorado support group and contact information for Jan Marie Smith, who is coordinating the meeting, if you think you want to attend. Dr. Theo Theoharides is going to be speaking at the meeting (May 5th), and might have some helpful ideas from his research. A GI doctor who treats SM patients might also be there.
If you have any other questions, feel free to ask!