His role has been dissolved as part of a restructure aimed at focusing resources on client-service staff, said EMEA managing director Andrew McGregor.
West, who was unavailable to comment as PRWeek went to press, was only promoted to his role in January. He previously held McGregor's current post.
'Andy was a very valued person in the business and this was not a decision that was taken lightly,' McGregor said.
Text 100 is part of the Next Fifteen group, which last month reported strong half-year figures (PRWeek, 7 April). Letting West go at a time when the agency is performing well could be a shock to some staff, an industry insider told PRWeek.
But McGregor denied the move was unusual and said it was purely aligned with the restructure. He said no further redundancies were planned across the firm's global network.
West played a major role in helping set up Text 100, which employs nearly 500 people across the world at its offices in the US, Australia, Japan and mainland Europe.
He had reported to New York-based chief executive Aedhmar Hynes.
Responsibility for the firm's global regions is split among three postholders. As well as McGregor, the team comprises Asia-Pacific managing director Ava Lawler, and North America managing director Eric Ashman.