She replaces James Gordon-Mackintosh, who left last September to set up Hope&Glory with creative director Jo Carr, while managing partner Alan Twigg also left to set up Light Brigade.
Gabbie reports to Simon Matthews, CEO of Fishburn Hedges, and has been acting MD at Seventy Seven since October.
Matthews commented: ‘Nadia has years of experience in managing and growing consumer businesses. She has made an immediate impact with our clients and the rest of the Seventy Seven team.’
The news comes as Gordon-Mackintosh and Carr have announced the arrival of Adrian Chitty as third partner at Hope&Glory. Chitty was formerly associate director at Good Relations and among responsibilities will take on training and developing the agency team.