This is the second project from the estranged spouses that has been picked up during the development season. They recently sold the comedy Ten Years to NBC.
Skinny Girl centers on a reformed over-eater who has managed to lose weight to become the titular "skinny girl". She now works with her ex in a diner, where she struggles to deal with her food addiction, according to The Hollywood Reporter.
Cox and Arquette will produce the project with Mad Love writer/co-executive producer Rob Sheridan.
Earlier this month, Arquette revealed that he and Cox are "in the friend zone" and don't plan on getting back together.
Cox currently stars on Cougar Town.