The Simple toiletries brand is getting more complex by extending into premium territory with a new beauty product collection called Simple Therapy.

However, the 26-strong range will only be available at the company's new retail venture - a day spa in London's Covent Garden, which opened this week offering treatments designed for sensitive skin - or online via a website, simplespa.co.uk.

Brand owner Accantia said that it intended to roll out the spa concept to about 30 locations nationwide, but there were no plans yet to market the new product range through the ­company's more familiar retail customers.

Simple Therapy cleansers, toners, masks, moisturisers, eye creams and massage oils all contain marine plant extracts, are perfume and colour-free and are approved for sensitive skin by an independent dermatologist.

They all have a significantly higher price point than the brand's standard lines, starting at £15.

Their arrival follows a similar move by Unilever's Dove brand in June this year. It also spread its wings into the premium beauty market, opening spa premises and launching a collection of products under a Dove Spa banner, with prices ranging from £10 to £28.

Like the Simple Therapy range, these are only available through the spa itself or online. Industry experts believe that Accantia's move could pave the way for a more upmarket positioning for Simple.

"This could be an effective way of changing consumer perception of the brand," said one insider.

"It is already a trusted name in skincare, especially for those with sensitive skin, but it is seen as one for every day.

"It may be that stretching the Simple brand image upmarket will give greater credibility to any further premium launches in the mainstream market."

Tenlay Soanes, Accantia's strategic marketing and communications controller, said the key market for the new venture was working women aged 28 and over.