By Karen Pihl-Carey

Three biotech companies priced their public offerings, collectively raising more than $180 million, about half of what was originally anticipated.

A couple of the companies actually offered fewer shares than they registered in March to sell.

Texas Biotechnology Corp., of Houston, issued 5 million shares priced at $12.50 per share. The offering, expected to close Wednesday, will give the company gross proceeds of $62.5 million. With a higher stock price of about $19.75 per share at the time of registration, the company was expected to raise proceeds in the range of $100 million. (See BioWorld Today, March 10, 2000, p. 3.)

Corixa Corp., of Seattle, sold 1.9 million shares at $32 per share, raising the company gross proceeds of $60.8 million. The company had planned to sell 2 million shares of stock, and with a stock price of $51 at the time of registration, it would have raised more than $100 million. (See BioWorld Today, March 9, 2000, p. 3.)

And Aviron, of Mountain View, Calif., expects gross proceeds of $45 million in a public offering of 2 million shares at $22.50 per share. The company also will receive about $4.5 million more as the underwriters have fully exercised their option to buy 200,000 shares from the company to cover overallotments. The underwriters also purchased 100,000 shares from a selling stockholder. Aviron initially intended to raise about $125.6 million through a public offering of 3 million shares, priced at $44.44 per share. (See BioWorld Today, March 9, 2000, p. 4.)

Aviron also said American Home Products Corp. (AHP), of Madison, N.J., agreed to purchase 686,160 shares of Aviron common stock at $21.38 per share, the price equal to the net proceeds per share to the company in the public offering. Aviron had planned to issue 347,423 shares to AHP at $42.22 per share, but still raised the intended $14.7 million. Expected net proceeds to Aviron from both the offering and the AHP transaction will be about $60.7 million. The offering is expected to close this week.

All three companies have watched their stock decline in the passing weeks - the result of what analysts have called misguided investors who misinterpreted a statement by President Clinton and British Prime Minister Tony Blair concerning patents and the public availability of information derived from the Human Genome Project. Stocks are just now beginning to recover.

Texas Biotechnology's stock (AMEX:TXB) closed Friday at $13.937, up 56.25 cents, while Corixa's stock (NASDAQ:CRXA) closed at $35.25, up 62.5 cents. Aviron's stock (NASDAQ:AVIR) closed at $29.875, up 87.5 cents.

Texas Biotechnology sold its shares through an underwriting syndicate led by PaineWebber Inc. and Prudential Vector Healthcare Group, both of New York; First Union Securities Inc. in Charlotte, N.C.; and Sanders Morris Harris in Houston. Net proceeds will be used to fund further clinical development of the company's product candidates, including Novastan, as well as research and development and general corporate purposes. In February, Novastan received an approvable letter from the FDA for the prevention and treatment of thrombosis in patients with heparin-induced thrombocytopenia. The company expects to receive final approval in the second quarter, launching the product later this year. (See BioWorld Today, Feb. 23, 2000, p. 1.)

The company also has two compounds in Phase II development: sitaxsentan, an endothelin receptor antagonist being developed as a treatment for pulmonary hypertension and congestive heart failure; and TBC1269, a selectin antagonist being developed for the asthma market.

According to its registration statement, the company will have 39.39 million outstanding shares following this offering. It had $15.17 million in cash, cash equivalents and investments as of Dec. 31.

Corixa offered its shares through underwriters led by Warburg Dillon read LLC, Lehman Bros. Inc. and Prudential Vector Healthcare Group, all of New York, and Pacific Growth Equities Inc., of San Francisco. The underwriters have an option to purchase up to an additional 285,000 shares to cover overallotments. If they exercise the option in full, Corixa and selling stockholders would raise an additional $9.12 million.

Prior to the offering, the company had about 18.9 million shares outstanding. The company had $780,000 in cash as of Dec. 31.

In its registration statement in March, Corixa said it intends to use the proceeds to fund product development and clinical research, as well as make acquisitions of technologies or companies. It hopes to soon file a biologics license application for Melacine, a melanoma vaccine. In its pipeline, it has RC-529, a next-generation synthetic adjuvant; MPL, an adjuvant immunostimulant for potential application in vaccines; and RC-552, a synthetic compound for use in protecting against reperfusion injury in patients undergoing cardiac surgery or angioplasty. It also has AnergiX.RA, a synthetic peptide vaccine for rheumatoid arthritis, that is in a Phase I/II trial.

Underwriters for Aviron's offering include Morgan Stanley Dean Witter and Bear, Stearns & Co. Inc., both of New York, and U.S. Bancorp Piper Jaffray, of Minneapolis.

The company said net proceeds from the offering will go to finance a regulatory filing for FluMist in the fourth quarter of this year as a preventive treatment for influenza in children and adults. Proceeds also will go to producing and testing validation lots, manufacturing and commercialization expenses of FluMist in its current formulation and development of a liquid form of FluMist, as well as to the research and development of other pipeline products, the development of infrastructure to support the activities, the potential development of additional manufacturing capacity and other general corporate purposes.

Aviron had about 16 million outstanding shares and $52.3 million in cash, cash equivalents and short-term investments as of Dec. 31.