Harper has been working as an in-house consultant for brand teams at AstraZeneca and Schering Plough for the last 18 months.
His previous agency post was as head of the communications division of international healthcare shop Pope Woodhead and Associates, where he was responsible for growing and managing the business.
Harper started his career in PR at Athena in 1997, where he was recruited from pharma firm AstraZeneca.
Harper will report into newly-installed MD Dr Steve Carroll. Carroll joined the agency last month, succeeding long-standing MD Cherry Wood, who resigned after 11 years to launch her own agency (PRWeek, 15 September 2008).