Chairman Mike Copland is reducing his role to two days a week from next year, and vice-chairman Jonathan Simnett - who has been with the firm for 17 years - is set to leave as of 31 December when his role will be made redundant.
Copland confirmed three other staff - at account director and associate director level - are also being made redundant in a response to the tech slump.
The move marks Brodeur's second wave of redundancies in the UK after bosses axed nine jobs earlier this year.
MD Simon Ward, who joined in March (PRWeek, 1 March), will take more of a lead role within the group's UK operations, assuming some of Simnett's responsibilities as vice-chairman.
Copland said the agency's structure had become too top-heavy, prompting a need to boost client-facing teams.
'The costs we had associated with senior people means we can now redirect our resources and have plans to hire more people at a junior level,' he said.
Simnett, promoted to vice-chairman in 2000, was unavailable for comment, but is understood to be considering his options outside the agency, alongside possible roles within the wider Omnicom group.