"So far ASOS is proving resilient to the slowdown in consumer spending and sales for the seven weeks to November 16 2008 are 104 percent ahead year on year," it said.
"We view the coming months with cautious optimism."
The group, formerly known as As Seen on Screen, also said it sees a "huge growth opportunity" from international expansion.
To this end it has appointed Jon Kamaluddin, currently Finance Director, to the role of International Director, although he will continue in his current role until a replacement is found.
For the six months to September 30 ASOS made a pretax profit of 4.1 million pounds up from 2.4 million pounds in the same period last year.
Its sales increased 107 percent to 65.7 million pounds, boosted by strong performances from tartan dresses, riding coats, platform shoes and statement jewellery.
International sales were up 252 percent to 11.4 million pounds.
First-half gross margin was up 80 basis points to 46 percent.
ASOS ended the period with cash of 8.9 million pounds.
Many retailers are struggling as consumers cut back on spending amid rising unemployment, falling house prices and growing fears of recession. But ASOS has been bucking this trend, benefiting from a young core customer base and the migration of retail spending from the high street to the Internet.
As of October 31, the ASOS.com website had 1.88 million registered users and 0.95 million active customers.
The ASOS.com site targets Internet-savvy 18 to 34 year olds looking to emulate the designer looks of celebrities such as Kate Moss, Paris Hilton and Victoria Beckham, but at a fraction of the price.
The second most visited clothing site after Next's, offers over 19,400 branded and own-label fashion products across womenswear, menswear, footwear, accessories, jewellery and beauty.
Shares in ASOS, which have increased in value by 39 percent over the last year, closed on Friday at 257 pence, valuing the business at 187 million pounds.
