Judd Apatow’s next project will see Leslie Mann and Paul Rudd reprise their “Knocked Up” roles in an untitled laffer set for summer 2012.Apatow will write and direct the film, the first he’s helmed since 2009′s “Funny People.” Apatow, Barry Mandel and Clayton Townsend will produce. In “Knocked Up,” Mann played Katherine Heigl’s older sister, who is married to Rudd’s character. Plot details are vague, and it’s not clear whether Heigl or Seth Rogen would reprise their roles from 2007′s “Knocked Up,” one of Apatow’s biggest successes with $200 million in worldwide box office. Universal will distribute, and production will begin this summer for a June 1, 2012, release. Mann and Rudd have had supporting roles in nearly every film Apatow has directed (Rudd was not in “Funny People”) and have appeared in numerous pics he has produced. Rudd will be seen next in “Wanderlust” and “My Idiot Brother,” the latter of which premieres at Sundance. Mann has a handful of projects due out in 2011 including “The Change-Up” with Ryan Reynolds and Jason Bateman. Mann is repped by CAA and Rudd is repped by UTA and Brillstein. Apatow is repped by UTA.