By Randall Osborne

Encouraged by an interim analysis of data, Xoma Corp. plans to complete by mid-1998 its Phase III pivotal clinical trial for Neuprex as a treatment for meningococcemia, a rare but potentially deadly childhood infection.

A data safety monitoring board that reviewed results from the trial found no safety concerns. The board analyzed data on the first 65 patients. More than 80 patients have been enrolled in the 200-patient trial at 17 medical centers in North America and the United Kingdom.

Xoma, of Berkeley, Calif., has treated more than 500 patients with Neuprex in clinical trials. None have shown evidence of that the drug might be unsafe.

Meningococcemia, a blood-borne bacterial infection caused by the same germ that is responsible for meningitis, strikes during colder months in the Northern Hemisphere. The inflammation response triggered by the flu-like ailment may progress within hours to cause shock, organ damage and death.

Antibiotics can deal with Neisseria meningitidis, the bug responsible for the disease, but poisonous endotoxin is released from the bacteria's cell walls as they die. Neuprex, a recombinant bactericidal and permeability-increasing protein, binds to the endotoxins, neutralizing and clearing them, while also killing the gram-negative bacteria and enhancing the work of antibiotics.

Patrick Scannon, Xoma's chief scientific and medical officer, said the Phase III trial should be finished in the second half of next year.

"[Meningococcemia] is really a seasonal disease, and the fall is the biggest time," he said. "We started in the middle of the season, so we'll have the full season this year, and we added a lot of hospitals over the summer."

Xoma's researchers have examined other diseases and "when you do," Scannon said, "you start seeing this common pathogenesis" against which Neuprex might be effective.

In September, the company began a Phase I study of Neuprex for cystic fibrosis patients and a Phase III trial in patients suffering severe hemorrhage from trauma is planned for later this fall.

"We're putting some final touches to the Phase III protocol, which we hope to start in a few weeks," Scannon said. The company is completing a Phase II trial of the drug against complications from liver surgery.

Xoma's stock (NASDAQ:XOMA) closed Wednesday at $7.75, down $0.062. *