Holden, who was promoted to MD in 2014, is to leave John Doe on 29 March to "take up a new challenge", the agency said.
Trewhella previously worked at John Doe as senior account director and for the past five years has headed up marketing for Pernod Ricard’s gin, Scotch whisky, Champagne and cognac brands. He has also worked at Exposure and content marketing agency Protein.
Trewhella will report to John Doe CEO Rachel Bell, who said: "It’s fantastic to be bringing Gin back to the agency. He’s a passionate brand marketeer who brings an exciting blended skill-set of marketing, content and comms. His arrival marks a new phase in the agency’s development."
John Doe was founded in 2009 by former Shine Communications creative director Rana Reeves, who left the agency’s New York office in 2016 and later founded an agency called Storey in the Big Apple, which is part of production firm North Six. The New York office closed with Reeves' departure, although John Doe still has an overseas presence via its partner network.
John Doe’s clients include Adidas, Itsu and Absolut. It employs 15 people and generates annual revenue of £1.6m, the company said.