How can I remove all special chars from UTF8 text in c#?

I would like to remove all special characters from my UTF8 text, but I can't find any matching regular expression.

My text like this:

ASDÉÁPŐÓÖŰ_->,.!"%=%!HMHF

I would like to remove only these chars: _->,.!"%=%!

I tried this regex:

result = Regex.Replace(text, @"([^a-zA-Z0-9_]|^s)", "");

But it removes my uft8 chars also.