She reports to managing director Nicky Walsby and started her new role last week.
Von Ahlefeldt has more than 25 years' experience in health comms and left W20 in June this year after just over a year at the agency.
During her career she has held senior roles at Tudor Reilly, Bell Pottinger Health, Porter Novelli, Ruder Finn, Manning, Selvage & Lee and Compass Communications.
Her father, James Kantor, was Nelson Mandela’s lawyer and she is one of the late South African leader’s goddaughters.
Von Ahlefeldt has a particular interest in advancing the diversity, equality and inclusion agenda and was the EMEA chair of the DE&I working group during her time at W20.
Walsby commented: “Tanya’s credentials are first class. In today’s landscape of increasing health inequity, heightened and highlighted through 2020 by the pandemic and global social unrest, the DE&I agenda is critical for our team and our clients.”
She added: “Tanya’s deep personal and professional experience in this area will bring a new level of thoughtfulness to both our corporate client assignments and our own employee experience.”
She is one of four new hires announced by the agency, all of whom have started in the past week.
Chiara Ennas, a former senior account director at M&F Health, has been brought in as a senior account director, while Rand Mashal, former global content and medical education project manager at Pfizer, has joined as an account manager.
Lucinda Kingham has moved from Edelman’s UK corporate practice, where she was an account manager, to join Syneos Health as account manager.
Syneos Health Communications employs more than 160 staff and has an estimated annual revenue of £18m.
It is ranked 19th in PRWeek's rankings of the UK's Top 150 PR consultancies in 2020. The agency is second placed in the 2020 rankings of healthcare agencies in the Top 150.
Its clients include pharma firms AbbVie, UCB, Novo Nordisk and Ferring.
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