(ShareCast News) - Online clothing retailer Boohoo.com reported a 39% increase in interim profit, with revenue up sharply as the company gained new customers.For the six months to 31 August, Boohoo posted a pre-tax profit of £6.27m from £4.5m in the same period last year, on revenue of £90.78m, up 35%. The number of active users rose 32% from last year to 3.5m.Earnings per share came in at 0.45p, up 55% from the first half of 2014.Joint chief executive officers Mahmud Kamani and Carol Kane said: "We are pleased to report a successful first half, with strong revenue growth driven by acquiring new customers through our investments in price, promotions and marketing spend."We continue to invest in our brand internationally and our strategy to focus on key markets where we see the greatest growth potential remains unchanged."Boohoo said the autumn/winter marketing campaign #WeAreNow is supporting a good start to the second half. In addition, the company said it was pleased with the response to its new app and responsive websites and will continue to invest in building customer value and market reach in the second half of the year.At 0945 BST, Boohoo shares were up 4.6% at 34.50p.