Comedian Hunter Cope is set to join Nicholas Braun in the Lionsgate laffer “Gay Dude,” and “Modern Family” thesp Sarah Hyland is also in negotiations for a key supporting role.Story follows two guys who make a pact to lose their virginity before their high school prom, only to find their friendship put to the test when one of them comes out of the closet. Cope will play the title character, while Braun will play his straight friend who goes to great lengths to find him a boyfriend. Hyland is in talks to play Braun’s prudish girlfriend. Chris Nelson (“Ass Backwards”) is directing from a script by “Parks and Recreation” scribe Alan Yang. Laurence Mark and David Blackman are producing for Laurence Mark Prods., while Jai Stefan is also producing. In addition to being a steady contributor to Funny or Die, Cope is a screenwriter and short filmmaker who co-founded the sketch-improv comedy troupe LAWV Chillers, which has performed at the Edinburgh Fringe Festival. Hyland, who got her start playing Howard Stern’s daughter in 1997′s “Private Parts,” can currently be seen as Haley Dunphy on ABC’s “Modern Family.” Thesp recently wrapped the Disney Channel pic “Geek Charming” and is currently filming the indie comedy “Struck By Lightning” with “Glee” star Chris Colfer. Cope is managed by Principato-Young. WME and RKM rep Hyland.