UPDATE 1-TranS1 Inc IPO raises $82.5 mln, above range

(Updates with initial market capitalization, use of proceeds, details of business)

NEW YORK Oct 16 (Reuters) - TranS1 Inc, a company that develops products for sufferers of lower back pain, raised $82.5 million in an initial public offering on Tuesday, above expectations.

The offering of 5.5 million shares sold for $15 per share, compared with a forecasted range of $12 to $14, according to an underwriter.

The company, which specifically develops treatments for the degeneration of the spine, is expected to begin trading its shares on Nasdaq on Wednesday under the symbol "TSON." (TSON.O).

It said it intends to use proceeds from the offering for sales and marketing, and to support research, development and the costs of seeking regulatory approval for some products.

Some of the company's products are commercially available in the United States, or Europe, while others are still in the process of winning regulatory approvals.

Based on its offering price, the Wilmington, North Carolina company will have an initial market capitalization of $281.5 million.

For the six months ended June 30, TranS1's revenue more than tripled to $7 million from $2.2 million during the same period a year earlier. The company's net loss of $4 million compared with a loss of $4.6 million during the half-year period in 2006.

In an amended filing with the U.S. Securities and Exchange Commission, TranS1 said it expects the market for its products to grow to $1.8 billion by 2011, from $1.4 billion last year, based on projections by Millennium Research Group. And the rise of minimally invasive spine procedures, such as those the company is developing, could accelerate market growth, it said in its filing.

Underwriters, led by Lehman Brothers and Piper Jaffray have the option to purchase an additional 825,000 shares to cover overallotments. (Reporting by Lilla Zuill)