The agency will be responsible for direct mail, sales promotions and electronic and trade advertising across the UK, mainland Europe and the US. Its remit covers everything from existing products to launches.
Part of Joshua's brief will be to promote the Aquafresh Extreme Clean variant: a foaming toothpaste, which was launched in the UK more than 18 months ago.
GSK's rival Colgate-Palmolive is set to launch a similar product, called Colgate Oxygen, in April. Joshua will work closely with sister agency Grey Worldwide on activity to stave off competition from Oxygen.
Other Aquafresh products include its range of herbal and fruit-flavoured toothpastes, which were launched last autumn with TV ads created by Grey London.
GSK's direct agency roster includes Billington Cartmell, OgilvyOne, The Marketing Store and WWAV Rapp Collins. Joshua's appointment is part of an overhaul of GSK's 拢25m direct business, announced last summer.
Colgate Oxygen's launch will be backed by a multimillion-pound ad campaign created by Rainey Kelly Campbell Roalfe/Y&R. It is the brand's first extension since Colgate Sensitive was introduced in 2003.
GSK and Colgate-Palmolive account for more than 75% of UK toothpaste sales, in a market worth almost 拢300m, according to Mintel.
GSK owns Aquafresh, Sensodyne and Macleans, while Colgate-Palmolive's brands include Colgate Total and Colgate Whitening.
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