Washington Editor

GTC Biotherapeutics Inc. expects to raise $15 million by selling 6.4 million shares of its common stock at $2.34 per share.

The shares are being offered under GTC's $40 million shelf registration statement filed with the SEC in late December. GTC's stock (NASDAQ:GTCB) fell 16 cents Tuesday to close at $2.35.

Proceeds would be used to support general corporate purposes, including the ongoing development of the firm's lead candidate, ATryn, a recombinant form of human antithrombin currently under review in Europe for use in patients with hereditary antithrombin deficiency.

The Framingham, Mass.-based company is in discussions with the FDA about the regulatory and clinical strategy for ATryn in the U.S. Thomas Newberry, the firm's vice president of corporate communications, told BioWorld Today GTC hopes to have the matter settled by the end of June.

As of Dec. 31, GTC had about $31.1 million in cash and short-term marketable securities with about 32 million outstanding shares (following the stock sale, the firm will have 38.4 million outstanding shares).

GTC's 2004 burn rate is expected to be less than $20 million. However, that burn rate might be adjusted as the firm is not certain whether it will be required to conduct additional trials in heredity antithrombin deficiency in the U.S. Meanwhile, GTC anticipates studying ATryn in severe burns.

The worldwide market opportunity for both indications is estimated at $300 million to $500 million, the company said.

Discovered by GTC, ATryn is proposed for use in people whose bodies don't produce enough of the protein antithrombin, a genetic defect blamed for the easy development of blood clots. Under normal circumstances, those people manage their condition with chemical-based blood thinners, which could cause excessive bleeding during surgery or childbirth.

Newberry said the company believes ATryn could be used during the duration of surgery.

The company identified ATryn using its transgenic technology designed to produce large volumes of proteins as well as proteins that normally are difficult to express in a traditional cell culture system, typically mammalian.

"ATryn, like many blood proteins, doesn't express well in a traditional bioreactor setting," Newberry said. "So our discovery' per se is that this is a protein that would be very difficult for other recombinant manufacturers to produce."

GTC is in partnering discussions for ATryn in Europe but also is considering launching it with a sales force of about 12 people.

Beyond the lead candidate, GTC is developing rhSA, a recombinant form of human serum albumin, for use as an excipient (a nonactive component used as a stabilizer in biological formulations). That is being developed in conjunction with Fresenius AG, of Bad Homburg, Germany.

GTC believes it will commercialize rhSA within two to three years, depending primarily on the level of development funding devoted to the program.

SG Cowen Securities Corp., of New York, was lead placement agent, and Rodman & Renshaw, LLC, also of New York, also acted as placement agent for the offering.