Synergen Inc. has started Phase III trials of its Antrilinterleukin-1 receptor antagonist to treat sepsis.

The Boulder, Colo., company (NASDAQ:SYGN), which made theannouncement Monday at the 12th Annual Cowen & Co. HealthCare Conference in Boston, expects to complete the eight-country study this year and file for marketing approval in1993.

The company's shares fell $1.13 to $49 in response to negativecomments by SoundView Financial Group analyst Larry Bloom,who lowered his recommendation to "short-term sell" from"hold."

Bloom said that an article in the March Journal of Immunologyshowed that IL-1ra exacerbates Listeriosis, a gram-positiveinfection, in mice. Although the researchers didn't use Antril,"the monoclonal antibody they used was a relevant proxy forAntril," Bloom told BioWorld.

Several other analysts disputed Bloom's analysis.

"It would be stretching it to draw any firm conclusions fromthis," said Margaret McGeorge of Sutro & Co. "They may begetting complement-mediated cell lysis caused by the antibody.So they might be killing off T cells. With Antril, you don't havea complement-mediated situation."

"We believe that to equate side effects caused by a monoclonalantibody versus IL-1ra is entirely without merit," wroteanalyst Mark Simon of Robertson, Stephens & Co. "Moreover,this occurrence did not develop in humans with IL-1ra, whichis the critical issue."

"The study didn't involve antibiotics," said Synergenspokeswoman Debra Bannister. "We're trying to combat thecytokine side effects of sepsis while giving the antibiotics timeto take hold. In this model, mice were challenged with listeriaand not given antibiotics at all."

Bloom also said the company should be valued in the $800million to $900 million range, compared with its presentmarket valuation of $1.2 billion. He rated the stock a "sell"down to $32. -- Karen Bernstein

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