TranS1, a medical device company, has filed plans for an initial public offering.

In a filing disclosed Tuesday, TranS1 said a price for stock and the number of shares to be offered had not been set. However, Private Equity Wire reported TranS1 hoped to raise $80.5 million.

The company has raised some $40 million in venture funding since it was launched in 2000. Backers include Advanced Technology Ventures, Delphi Ventures, Cutlass Capital, Sapient Capital and Thomas Weisel Healthcare Venture Partners.

The IPO will be handled by Lehman Brothers Inc. and Piper Jaffray & Co. Co-managers are Cowen and Company, LLC and Leerink Swann & Co.

TranS1 has developed a device for treating degenerative disc disease that requires minimally invasive surgery.