J. Walter Thompson already handles some of the drug firm's business, but the injection of the much larger accounts handled by Bates will give the agency a much larger role in Pfizer's marketing.
It will also end recent speculation that the relationship between JWT and Pfizer has been bumpy. JWT recently lost the Lubriderm arthritis drug Celebrex accounts to rivals.
The move of the Pfizer business follows WPP's acquisition of Bates parent Cordiant last week. WPP has already shifted some Bates accounts including the £32m DIY retail chain B&Q over to JWT.
In London JWT will also pick up Pfizer's Bates accounts, which are valued at more than £5m and include Benylin and Sudafed.
JWT in New York is adding Pfizer brands including Benadryl, Visine and Rolaids along with around 125 Bates staffers who work on Pfizer. JWT already handled Pfizer brands, including Listerine and Efferdent, which together generate around $200m in billings.
The influx of staff and the swelling of its pharmaceutical and healthcare related business comes as WPP launches a health-care related unit, which is being called Health@JWT.
The new unit will be based in New York and underlines the growing importance of the healthcare sector to the advertising businesses.
During the battle for Cordiant, one of the most hotly sought assets was its Healthworld business. Last year WPP's Ogilvy & Mather strengthened its healthcare business with the integration of the Shire Health Group into the O&M Europe, Africa and Middle East business.
WPP plans to roll out the Health@JWT brand across the JWT network and shortly will see it launched in London and in other markets.
Other Bates business set for JWT includes the £8m Roche business, including the Rennie and Sanatogen briefs, as well as the private banking firm HSBC Republic, Hoover, Thames Water, Piaggio and Duchy Originals.
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