Format: 

Producer, A. A. (Producer). (Year, Month Day). Title of work [Description of form]. Retrieved from URL

Examples: 

National Public Radio (Producer). (2015, April 13). Game of Thrones fans develop formula to determine who might survive series [Segment transcript]. Retrieved from http://www.npr.org/2015/04/13/399414406/game-of-thrones-fans-develop-for...

In-text: (National Public Radio, 2015)

Notes: 

[Description of form] refers to the original type of form the transcript information appeared in. Examples given in the APA manual are [Podcast transcript], [Speech transcript], [Interview Transcript]. Adapted below is [Segment transcript] for a segment which appeared on NPR's website.

Source:
APA (ER) - p. 27, no. 55