The property, which is owned by the Churchill Group, will be renamed the Churchill Hyatt Regency from 1 May.
Michael Gray has been appointed general manager at the hotel following close involvement in the search for a London property for Hyatt. Gray was formerly general manager at Hyatt's Carlton Tower.
Hyatt International is undertaking an 18-month renovation of the 445-room property. Meeting facilities, guest areas and back-of-house areas will be refurbished.