The production, which is directed by Matthew White (Sweet Charity,Top Hat), runs from 2 December 2013 to 22 February 2014 (previews from 23 November).
Dreyfus is best known from TV roles in The Thin Blue Line and Gimme Gimme Gimme, but his extensive theatre credits include Cabaret, The Producers, Breakfast at Tiffany's, The Common Pursuit and Lady In The Dark at the National, for which he won an Olivier Award.
Clune has most recently played Violet in the national tour of the musical 9 to 5. Her other stage credits include the international tour of Mamma Mia!, playing Mrs Wilkinson in Billy Elliot at the Victoria Palace Theatre and Mogadishu at the Lyric Hammersmith.
As previously reported, others in the cast are Fra Fee as Candide, Cassidy Janson as Paquette, Ben Lewis as Govenor and Vanderdendur, Scarlett Strallen as Cunegonde and David Thaxton as Maximillian.
Based on Voltaire's 1759 novel, Candide has music by Leonard Bernstein, and a book which was originally adapted by Hugh Wheeler, then adapted again by Robert Carsden and Ian Burton. The lyrics are by Richard Wilbur with additional lyrics by Stephen Sondheim, John Latouche, Lillian Hellman, Dorothy Parker and Bernstein.
Candide premiered on Broadway in 1956 at the Martin Beck Theatre, starring Barbara Cook.
The Menier revival is choreographed by Adam Cooper, whose choreography credits include On Your Toes (Leicester Haymarket & Royal Festival Hall), Carousel (Savoy) and Grand Hotel (Donmar).
The creative team also includes David Charles Abell (Musical Supervision), Paul Farnsworth (Set & Costume Design), Paul Anderson (Lighting Design), Gareth Owen (Sound Design), Seann Alderking (Musical Direction) and Jason Carr (Orchestrations).