Immunex Corp.'s Pixykine failed to show significantbenefit in restoring platelets compared to the company'sLeukine drug in a Phase III trial in bone marrowtransplantation. Analysts said the results were not asurprise.

Pixykine, a fusion protein composed of forms ofinterleukin-3 and granulocyte macrophage-colonystimulating factor (GM-CSF), was tested in a 177-patienttrial against the white blood cell stimulant, Leukine(yeast-derived GM-CSF ), in patients receiving a bonemarrow transplant for non-Hodgkin's lymphoma. Primaryefficacy endpoints were time to recovery of platelets andneutrophils.

"In earlier Phase I/II studies with Pixykine in thetransplant setting, the drug showed accelerated recoveryof white blood cells, platelets and red blood cells," saidPeggy Phillips, senior vice president for pharmaceuticaldevelopment at Immunex. "At some centers in the PhaseIII study, a similar improvement was noted. However,when data from all centers in the randomized, controlledsetting were combined, Pixykine did not outperformLeukine."

Results from another Phase III trial, comparing Pixykineto GM-CSF in a high-dose chemotherapy setting, areexpected to be available early in 1996, the company said.

The initial Pixykine results were released late Thursday.Immunex's stock (NASDAQ:IMNX) lost $1.13, or 8percent, to close Friday at $12.38.

"It's a disappointment, but not totally surprising,"Matthew Geller, an analyst with New York-basedOppenheimer & Co., said of the results. "It's a tougharea. Immunex has always been a company with goodscience but it's never had luck on its products."

Ed Hurwitz, an analyst with San Francisco-basedRobertson Stephens & Co., said the company's stockprice reflects the valuation of the current business, withvery little premium added to the pipeline. Hence the dropFriday wasn't as significant as other companies had withsimilar news.

"Nobody owned the stock because of Pixy," Hurwitzsaid. "I wouldn't expect Pixy to be a contributor in theforeseeable future. I think it had the best chance ofworking in bone marrow transplantation because that'swhere the Phase I/II data were best. I have lowerexpectations for the other studies. I think the Street sharesmy view unanimously."

Immunex, of Seattle, said it will wait until completeresults from the Pixykine studies are in before decidingthe future of the drug. If the data do not warrantcontinued development, Immunex will allocate resourcesto other programs: Leukine for infection, Novantrone inprostate cancer, and three products expected to enter theclinic next year _ FLT3 ligand, interleukin-15 and CD40ligand.

Robin Shapiro, the company's manager of corporatecommunications, suggested one option for the drug: "Exvivo expansion of Pixykine has generated commercialinterest from companies pursuing cell separationtechnologies, particularly in combination with othercytokines."

She said, "We've positioned the company for financialsuccess and we're progressing toward that. We neverrelied on the success or failure of one product. Immunexis a fully integrated biopharmaceutical company withproducts and a pipeline that has both near- and long-termopportunities. The data today is one step of many inImmunex's life."

American Home Products, of Madison, N.J., owns 55percent of Immunex, which last week released its thirdquarter numbers.

Immunex had cash and marketable securities of $14.3million on Sept. 30, 1995. Its losses for the first ninemonths of the year were $9.1 million on revenues of $115million. n

-- Jim Shrine

(c) 1997 American Health Consultants. All rights reserved.