AMC Chief Executive Adam Aron said he believes David Ellison will hold to his promise of making 30 films a year from the combined Paramount-Warner Bros. company.
Despite striking a one-year deal with Byron Allen, "we are still going to develop other ideas, other concepts," said George Cheeks, the chair of TV Media at Paramount.
The letter was signed by nearly 1,000 artists and movie creators, including Ben Stiller, Bryan Cranston, Noah Wyle, Joaquin Phoenix, Kristen Stewart and Jane Fonda.
Paramount President Jeff Shell is expected to exit the company after being entangled in a legal battle with a controversial Las Vegas gambler and self-styled "fixer."