Daniel Cudmore, who first appeared as iconic mutant Colossus in X2: X-Men United and reprised the role for X-Men: The Last Stand and this past summer's X-Men: Days of Future Past, feels pretty confident that the character will not return in the next installment X-Men: Apocalypse. This has not been confirmed by 20th Century Fox. It is possible that the studio is planing to recast a younger version for the movie.
X-Men: Apocalypse is recasting younger versions of Storm, Jean Grey and Cyclops. While nothing has been announced by the studio at this time, it is possible that all of the characters from the earlier X-Men movies, with the exception of Hugh Jackman as Wolverine, are being recast. This latest adventure serves as the final chapter in the X-Men: First Class trilogy, and is bringing back stars such as James McAvoy, Michael Fassbender and Jennifer Lawrence.
Colossus does appear in the comic book storyline that will serve as a basis for X-Men: Apocalypse. His brother actually becomes one of Apocalypse's 4 horsemen, and the two siblings are forced to square off against each other. Its possible that the character is simply being written out of the script. The plot may be reconfigured to bring in a new mutant not yet seen in the franchise. There's always the chance that Daniel Cudmore will return for an X-Men movie in the future, though. And he does hope he can lock down a role in another 20th Century Fox Marvel movie, with his sights set on Deadpool. Here are his tweets.