Biodel issued a press release stating the have completed enrollment of two phase III trials of their new fast acting insulin. They also announced plans to build and operate a manufacturing facility.
As I understand it they are making a faster acting insulin. Faster would bolus better and shorten insulin on board times. It sounded interesting enough that when they issued an IPO I bought a few shares not so sure I would be the first person to sign their kids up to use it but time will tell.
Diabetes Health ran an article on c-peptides. Now I am the first to admit I don't know much other than c-peptides are used in diabetes diagnosis to distinguish between T1 and T2. This article is a nice little primer on c-peptides.
The article suggest thinking has been they don't do much. My thought is regardless of your thought on evolution or creation why would either have something being produced that doesn't do anything? More likely we just don't know what it does yet.