By Jim Shrine

ICOS Corp. began a Phase III trial of LeukArrest, its first product to reach that stage of development, in patients with acute ischemic stroke.

Bothell, Wash.-based ICOS said the randomized, double-blind, placebo-controlled study of the humanized antibody is expected to include 800 patients in North America.

LeukArrest, formerly called Hu23F2G, is an inhibitor of cell-adhesion molecules, designed to block movement of leukocytes from the bloodstream into inflamed tissue.

Initially, two doses of the drug and placebo will be tested, following standard stroke treatment. After an interim analysis, only the better-performing dose will continue being tested against placebo. The primary endpoint is functional ability, as measured by four neurological assessment scales.

"It's going to be a big year for us," said Lacy Fitzpatrick, ICOS' associate director of investor relations, noting the company could have three products in Phase III trials in 1999. One of those trials would be with LeukArrest in hemorrhagic shock. The third product is IC351, a male erectile dysfunction drug being developed with Indianapolis-based Eli Lilly and Co.

Fitzpatrick said Phase II results of LeukArrest in ischemic stroke patients warranted the move into Phase III trials. The maximum tolerable dose, 1.5 milligrams per kilogram of body weight, given twice over three days, resulted in a response rate of 80 percent as measured by the National Institutes of Health Stroke Scale.

Michael Deeley, director of LeukArrest development at ICOS, said enrollment is expected to take at least a year, with a 90-day follow-up period included in the trial. "We'll also follow them out six months and a year to collect as much data as possible," he said.

The extended follow-up period won't delay results, however. "We'll give guidance later as to which quarter next year results will be available," Fitzpatrick said.

LeukArrest also is being developed for myocardial infarction and multiple sclerosis (MS). Enrollment is continuing in a 420-patient Phase II study in myocardial infarction, and a multidose Phase II study in MS is nearing its end.

ICOS disclosed the start of the LeukArrest Phase III trial along with its earnings Monday. The company recorded a net income of $58.5 million for the fourth quarter, or $1.22 per share, and $31.3 million for the year, or 67 cents per share. Those numbers, which came in below analysts' estimates, are attributable to a $75 million payment made by Lilly, upon formation of a joint venture to develop and market IC351, a phosphodiesterase type 5 inhibitor. (See BioWorld Today, Oct. 2, 1998, p. 1.)

Lilly is paying another $52 million to capitalize that joint venture.

Other products in ICOS' pipeline are Pafase, a human protein in Phase II studies in pancreatitis indications and acute respiratory distress syndrome; ICM3, a humanized antibody in multidose Phase I/II studies in Europe and in the U.S. for psoriasis; and IC14, a chimeric antibody for septic shock, which recently was taken into human studies.

ICOS' stock (NASDAQ:ICOS) lost 93.75 cents per share Monday, closing at $26.50. n