• Adnexus Therapeutics Inc., of Waltham, Mass., withdrew its registration statement for an initial public offering due to its pending $430 million acquisition by New York-based Bristol-Myers Squibb Co. Adnexus originally filed to raise up to $86 million in an IPO. (See BioWorld Today, Aug. 23, 2007, and Sept. 25, 2007.)

• Ambrilia Biopharma Inc., of Montreal, filed a short-form prospectus to raise C$15.6 million (US$15.9 million) through the sale of 12.5 million units, each comprised of one share and one-half of one warrant, priced at C$1.25 each. Underwriters, led by a syndicate led by Canaccord Capital Corp., and including Dundee Securities Corp. and Loewen, Ondaatje, McCutcheon Ltd., will have an overallotment option to purchase up to an additional 1.9 million units, which would add C$2.3 million to the proceeds. Ambrilia expects the offering to close on or about Oct. 30, 2007, and will use the fund to support ongoing Phase III trials of improved formulation of Octreotide, the development of its new formulation of Goserelin and further lead optimization of its series of HIV integrase inhibitors. Net proceeds also will support the company's other antiviral development activities and go toward working capital and general corporate purposes.

• Arena Pharmaceuticals Inc., of San Diego, filed for a proposed public offering of 10 million shares of common stock. A price has not yet been set, but based on recent prices, the company estimated the deal could generate net proceeds of about $102.7 million. Proceeds will be used for discovery, preclinical and clinical development of Arena's drug candidates for obesity, diabetes, thrombosis and insomnia, as well as for general corporate purposes and, potentially, acquisitions. CIBC World Markets and UBS Investment Bank are acting as joint book-running managers, and Arena plans to offer them the option to purchase an additional 1.5 million shares to cover any overallotments.

• SemBioSys Genetics Inc., of Calgary, Alberta, increased the underwriters' option associated with its current private placement from 375,000 units to 1.18 million units. Each unit is priced at $2.60 and consists of one common share and one-half of a common share purchase warrant. If the underwriters exercise their option in full, SemBioSys stands to get $9.6 million in gross proceeds, which will be used for preclinical and clinical development of plant-manufactured insulin and cardiovascular therapeutic products. The offering is expected to close on or about Nov. 14.