From TV Guide’s Mega Buzz:
Adam has been trapped in the cage on Supernatural since Season 5. Is he ever getting out of Hell? —Sarah
Unfortunately, Adam is not one of the many familiar faces returning to Supernatural this season, but there is some hope to see the third Winchester brother again. “As long as he’s in the cage, there’s always a chance,” showrunner Jeremy Carver says. “He’s not coming out tomorrow, but there’s always a chance.”