Sara Ramirez, Chandra Wilson, Justin Chambers and James Pickens Jr. will remain on the ABC medical drama for at least two more seasons.

Grey's Anatomy is locking in its core cast members for the future.

Sara Ramirez, Chandra Wilson, Justin Chambers and James Pickens Jr. have all inked new two-year deals to remain on board the ABC medical drama, The Hollywood Reporter has learned.

The new contracts will ensure that the quartet will remain on board the show from Shonda Rhimes and Betsy Beers through a potential 11th and 12th season, joining stars Ellen Pompeo and Patrick Dempsey. The latter duo signed new two-year contracts in January.

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Grey's Anatomy has undergone its fair share of casting changes this season. Emmy nominee Sandra Oh announced in August that she'd be departing the series at the conclusion of its 10th season. Her final episode airs May 15. Gaius Charles (Shane) and Tessa Ferrer (Leah), who boarded the show as recurring players and were promoted to series regulars ahead of season 10, will also exit this season as their contracts have not been picked up for Grey's Anatomy's expected 11th season.

Behind the scenes, co-showrunners Tony Phelan and Joan Rater exited after season 10 for a development deal with CBS Television Studios. Stacy McKee and Bill Harper will take over as co-head writers in place of Phelan and Rater and work alongside Rhimes.

For their part, Wilson (Bailey), Chambers (Alex) and Pickens (Weber) -- along with Dempsey (Derek) and Pompeo (Meredith) -- are the last remaining series regulars who have been with the show since the pilot and are due to return. Wilson also typically directs a few episodes of the series each season. Ramirez joined the show as a recurring player at the end of season two and was upped to regular for season three.

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The jury is still out if Caterina Scorsone, who plays Derek's sister Amelia, will return as a regular for season 11. She's currently reprising her role from former Grey's spinoff Private Practice for the final handful of episodes this season with the character's story line leaning toward a potential full-time return.

An official 11th renewal is expected to come next week.

Chambers is repped by Gersh, Anonymous Content and Jackoway Tyerman; Ramirez is with Mitchell K. Stubbs, Cornerstone and Schreck Rose; Wilson is with Abrams Artists Agency, Station3 and Jackoway Tyerman; Pickens is with Stone Manners, Wright Entertainment and Stone Meyer.

Email: Lesley.Goldberg@THR.com

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