Yes, integrated NT authentication with Sitefinity is supported, please take a look at this article
from our Documentation explaining how to properly set it up. If you need any additional information, please write back.
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items