Pinnington, who previously worked as commercial director at online network Doctors.net.uk, joins Edelman as head of digital health for Europe and is charged with expanding the agency's digital work across the EMEA region.
The appointment comes as agencies continue to get to grips with using digital and social media in the health and pharmaceutical arena.
Last month, pharma giant Bayer UK was reprimanded by the pharmaceutical industry regulator for using Twitter to promote prescription medicines to the public, in breach of the ABPI Code of Practice.
Over the past year, Edelman has been moving further into digital health, developing campaigns for clients including AstraZeneca, Novartis, and Novo Nordisk.
Commenting on Pinnington's appointment, Edelman's digital MD, Marcus Dyer, said strengthening the agency's digital health division was 'critical' to understanding clients' needs and that navigating the highly regulated environment was 'paramount'.
'The internet is the second most important source of health information for patients across Europe, while well over 60 per cent of doctors carry smart phones,' said Dyer.
He added: 'Those are pretty strong imperatives for pharmaceutical companies and anyone involved with healthcare to be thinking about how to engage in the online space.'
Before joining Edelman, Pinnington worked with a number of pharma firms and healthcare organisations on digital campaigns.