The resignations will be a huge blow for Agency Republic, Campaign's Digital Agency of the Year 2006, which will be losing two of the most renowned digital talents in the industry.
Griffith, who has been working for Agency Republic since 2005, said: "I'm planning to travel for three months but beyond that I’m not really sure what I'll be doing, probably something in London."
Sandoz, who was promoted to the role of executive creative director just one month ago, was unavailable for comment.
Jane McNeill, the managing director of Agency Republic, said: "Our joint creative directors Gavin Gordon Rogers and Gemma Butler will continue to lead the creative department in style. An announcement on the leadership of our well-established planning team will be made in due course."