I second Dot. Ask the person who told you this for a reference, a name, a web site, something to back his/her story. Please don't become an FTR'er.
Good question. But who told you this? Were they talking human or lab mice/rats? My elderly neighbor returns home from his morning coffee shop discussions with far out stories and swears not only they are true because "its heard/told by a very reliable source", but also that it didn't come from National Enquirer or Star paper articles.
I went searching; Roche Holding, the giant Swiss drug manufacturer, recently bought Disetronic Holding, the second largest maker of insulin pumps, but have been restricted from selling them in the U.S. until manufacturing issues have been resolved. Nothing in Roche to indicate a 15 day insulin.
I Google'd "15 day swiss insulin" and received 175,00 hits. Nothing in the first 5 pages to indicate a 15 day insulin. There was one on the results injected in 15 day old rats. haha. A "15 day insulin" search resulted in 477,00 hits. Again a big fat zero!
I searched the three largest insulin makers - Novo Nordisk, Eli Lilly, and Sanofi-Aventis - and found nothing.
So, unless someone corrects me with written proof, this 15 day Swiss insulin is a HOAX.