Jestico + Whiles' plans for Camden Town Tube station suffered a major setback last week when the borough's planning committee voted to oppose the controversial scheme.
Councillors condemned the five-storey building at the centre of the proposals as out of scale and harmful to the character and appearance of Camden's conservation area.
The mixed-use scheme has attracted opposition from residents and conservation groups, among them local MP Frank Dobson.
An inquiry has already been scheduled for February - brought by London Underground when Camden missed its target timescale for considering the scheme - and planners will now appear in opposition.
Planning officer Rob Brew said the design 'was not the standard we would expect'. He added that both the scale and form of the building were unacceptable and it 'lacked coherence'.
However, Jestico + Whiles project architect Alex Costa said he was continuing to develop an alternative scheme that would address the concerns. The five-storey office block had been softened, he said, and its 'horizontality' reduced. The top two storeys were now also set back around the building's entire perimeter.
Costa said the design team would be meeting with officers next week to discuss the revisions.
However, Brew said it was 'likely' that the second revised scheme, to be considered by Camden on 18 December, would also be recommended for refusal.