Its health division won the business after a five-way competitive pitch.
WA will provide support across multiple treatment launches, patient advocacy engagement, and helping the company establish its position with policy-makers.
Sanofi Genzyme works on treatments for challenging genetic diseases such as lysosomal storage disorders, as well as inherited neurodegenerative and ophthalmological diseases.
WA already works with Sanofi’s oncology business and has started work across the rare-disease portfolio with immediate effect.
Caroline Gordon, director and head of health at WA, is leading the agency’s work on the new account.
She said: “Sanofi Genzyme has an amazing heritage in rare disease, and we’re delighted to be supporting the next phase of its growth in the UK.”
Gordon added: “With the policy landscape supporting patient access to rare-disease diagnosis and treatment constantly evolving, Sanofi needs an agile, creative and well-connected partner – that’s right where WA sees itself.”
Commenting on the decision to hand the work to WA, Sophie Mansfield, public affairs and policy lead for rare disease at Sanofi, said: “WA has consistently shown us fresh ideas, thoughtful insights and lots of energy. I’ve been really impressed, and am confident that together we can continue to make progress for patients with rare diseases.”
The account win is the latest success for WA’s growing health practice, which recorded a 40 per cent increase in revenue in 2019 – a year in which it won new work in the areas of diabetes, generics and medicinal cannabis.
Bayer and Merck are among the agency’s other pharma clients.
Revenues at WA, which was founded in 1991 as Westminster Advisers and is one of the UK’s top 150 consultancies, rose 25 per cent in 2018 to £3.8m.
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