Axon previously worked at John Brown Publishing and joined River in September 2001 as group publisher. In his new role, he will continue to oversee publishing but will also develop River's growth strategy.
Axon will also review the commercial side of River's business and look at ways to grow the advertising sales operation.
Nicola Murphy, the managing director of River, said: "Ed has played a major role in growing the company and has been instrumental in securing new business, including Sunday Times Travel and Honda."
Other promotions include Kate Mowatt, who has moved up from account director to director of publishing and operations.
Elaine Bickell becomes group account director. She will oversee all River's accounts and develop and improve client services.
Vicki Scaife has joined from Teletext as group advertising manager. She will deputise for Robin Drysdale, River's advertising director.
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .