By Randall Osborne

To forge ahead with commercializing its drug for non-Hodgkin's lymphoma, Coulter Pharmaceuticals Inc. raised $60 million in a public offering of 2.4 million shares for $25 per share.

Coulter, of Palo Alto, Calif., had filed earlier this month with the Securities and Exchange Commission to sell 2 million shares, when its stock was selling for $27.50 per share, which would have raised $55 million. (See BioWorld Today, July 13, 1998, p. 1.)

The company's lead drug, Bexxar, is a monoclonal antibody conjugated to iodine 131. It attaches to a protein found only to the surface of B cells (including non-Hodgkin's and some normal B cells), in order to provide more concentrated radiation to tumor cells. Bexxar is known as a "hot" antibody, as opposed to the traditional "cold," unlabeled version of the same anti-CD20 antibody, and has outperformed the latter in clinical trials.

Coulter, which is collecting data from a Phase III investigational trial, plans to file a biologics license application with the FDA by the end of this year. Interim Phase III data reported in May were positive, with success rates — as measured by duration of response in patients with advanced disease — running about 77 percent. Coulter anticipated at least 51 percent.

Non-Hodgkin's lymphoma patients given chemotherapy often achieve remission, but they typically relapse and die from the disease or from complications of treatment. Under new guidelines adopted last year by the Nuclear Regulatory Commission, Coulter has been providing outpatient treatment with Bexxar, which is administered in a two-step regimen.

The drug, if approved, would be the first radioimmunotherapy in the U.S. for that indication. Last fall, Coulter raised $42 million in a public offering to support development of Bexxar. (See BioWorld Today, Oct. 13, 1997, p. 1.)

Coulter also is developing a tumor-activated peptide pro-drug version of doxorubicin to treat certain solid tumor cancers.

The $60 million offering was managed by BT Alex. Brown Inc., of Baltimore; Hambrecht & Quist LLC, of San Francisco; Pacific Growth Equities Inc., of San Francisco; and Piper Jaffray Inc., of Minneapolis. *