Both Panoply and Gimlet (two popular podcasting companies) are getting into that business to various degrees. Panoply recently co-produced and co-promoted a podcast with GE while Gimlet seems to be more focused on doing pure "white-label" podcasts where they'll do all the production work, but their name doesn't appear on the final product.

Basically if you are company and want a podcast they'll make it for you (or work with you to make it).