By Matthew Willett
ImmunoGen Inc. filed for the sale of 4 million shares Tuesday, a financing round that would raise $121.5 million at Tuesday's opening price of $30.37 per share.
An additional 600,000 shares were registered to cover underwriters' overallotment options. Underwriting the offering are SG Cowen Securities Corp., of New York; Robertson Stephens Inc., of San Francisco; and Adams, Harkness & Hill Inc., of Boston.
ImmunoGen's stock (NASDAQ:IMGN) rose 44 cents Tuesday, closing at $30.81.
ImmunoGen officials declined comment, citing SEC-imposed quiet period restrictions.
According to ImmunoGen's filing, however, the company plans to use the offering's proceeds for general corporate purposes, working capital and research and development expenses.
Founded in 1981, the Cambridge, Mass.-based company focuses on antibody-based cancer therapeutics. Its TAP (tumor-activated prodrug) technology platform utilizes small-molecule, cytotoxic drugs coupled with monoclonal antibodies to destroy cancer cells.
TAPs, the company said, offer high specificity and potency with minimal toxicity, in addition to high stability in their release.
After the offering, the company will have about 38.35 million shares outstanding. As of June 30, the company had about $17.33 million in cash, cash equivalents and marketable securities.
The company's lead candidate, huC242-DM1/SB-408075, is in two Phase I/II clinical trials for the treatment of colorectal, pancreatic and some non-small-cell lung cancers.
A second candidate, huN901-DM1, is designed to treat non-small-cell lung cancer, and is in preclinical study.
ImmunoGen has collaborated with SmithKline Beecham plc, of London, since February 1999 to develop and commercialize huC242-DM1/SB-408075. SKB has worldwide commercialization rights to the compound excluding the Far East in return for royalty payments on net sales for ImmunoGen and milestone payments worth up to $41.5 million.
To date, ImmunoGen received five milestone payments stemming from the agreement totaling $11.5 million, and for sale of stock to SKB ImmunoGen received an additional $2.5 million.
The Cambridge company also is collaborating with British Biotech plc, of Oxford, UK, in an agreement that covers commercialization and development of huN901-DM1 in Europe and Japan. ImmunoGen retained U.S. commercialization rights to the drug.
British Biotech is responsible for the drug's clinical development, and since the collaboration's inception in May has paid ImmunoGen $1.5 million. British Biotech also agreed to pay royalties on commercial sales of the drug after regulatory approval, which in the U.S. triggers a milestone payment from ImmunoGen to the Oxford company.
A second and a third collaboration in May, these ones with Genentech Inc., of South San Francisco, gave an exclusive license for the maytansinoid TAP technology for antibody product development targeting the HER2 antigen and for antibody product research, respectively.
Those agreements garnered ImmunoGen a $2 million up-front payment in addition to milestone payments that could total $40 million for the first agreement and a $3 million technology access fee plus milestones of up to $40 million per target for the second.
Most recently, in September, ImmunoGen agreed to a similar arrangement with Abgenix Inc., of Fremont, Calif., that provides Abgenix with access to TAP technology for use with Abgenix antibodies.
That agreement is estimated to yield the company about $5 million through technology access fees. Milestone payments and royalties could increase the total.
Further, Abgenix purchased $15 million of ImmunoGen stock in association with the September agreement.