Aviron Inc., which postponed its initial public offering last monthbecause of poor market conditions, is proceeding with a Phase IIIstudy of its lead product, an influenza vaccine, in collaboration withthe National Institutes of Health (NIH) in Bethesda, Md.

The double-blind, placebo-controlled trial is expected to enroll 900children, ages 1 to 6, by the end of the year to determine theeffectiveness of the vaccine to protect the youngsters from the flu thisseason, which normally sweeps across the U.S. from Novemberthrough March.

Vera Kallmeyer, Aviron's head of corporate development, said thecompany could have data in 1997, depending on the severity of theinfluenza outbreak. If the season is mild, the trial investigators likelywill enroll more children and continue the study next year. A separatePhase III study of the flu vaccine in adults is expected to begin in1997.

Kallmeyer said Aviron, of Burlingame, Calif., has targeted 1999 for apotential market launch of the product following application for FDAapproval.

The vaccine differs from current flu inoculations in two major ways.Aviron's product is delivered more conveniently in a nasal spray,rather than injected into the bloodstream. It also activates antibodiesagainst the virus in the mucosal immune system of the nasal passages_ where the flu usually first infects the body _ as well as thesystemic immune system.

Aviron's vaccine, which was licensed from the NIH under aCollaborative Research and Development Agreement, is derived froma cold-adapted, modified living influenza virus that has been alteredto make it non-virulent. It already has been tested in 7,000 people andhas proved safe.

Wyeth-Ayerst Laboratories, of King of Prussia, Pa., studied thevaccine from 1989 to 1993 before dropping development. Wyeth-Ayerst is a subsidiary of American Home Products Corp., ofMadison, N.J.

Aviron has a collaboration with South Korea-based Sang-A, asubsidiary of the Hanbo Group in Seoul, for manufacturing thevaccine and marketing it in Korea.

Kallmeyer said Aviron allowed its registration for the IPO to expire,but it expects to revive the offering when market conditions improve.In July 1996 biotechnology stocks slumped after a year-long surgeduring which companies raised a record $5.2 billion in follow-onofferings and IPOs.

Kallmeyer said Aviron currently has enough cash to supportoperations through March 1997, but expects to complete a privateplacement this fall for between $8 million and $12 million.

With the private placement financing, she said the company will beable to meet its goal of having four vaccines in clinical trials by theend of 1997.

In addition to the flu vaccine, Aviron expects to start a Phase II studyof a parainfluenza vaccine and two Phase I trials of vaccines againstEpstein-Barr virus, which causes infectious mononucleosis, andcytomegalovirus. The company is collaborating with London-basedSmithKline Beecham plc on the Epstein-Barr vaccine. n

-- Charles Craig

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