Aviron acquires rights to new influenza vaccine in simultaneous agreements with NIH and University of Michigan; vaccine delivered by nasal spray offers advantages for children and adults -- a key element in company's disease prevention focus.

BURLINGAME, Calif.--(BUSINESS WIRE)--March 8, 1995--Aviron Wednesday announced that it signed a Collaborative Research and Development Agreement (CRADA) with the National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH) and a licensing agreement with the University of Michigan to complete development of an intranasal influenza vaccine.

The individual components of the vaccine have already been studied in more than 7,000 people ranging in age from two months to more than 100 years and have been shown to be safe and effective, particularly in children, according to J. Leighton Read, M.D., chairman and chief executive officer. The announcement was made at the Raymond James & Associates Health Care Conference in St. Petersburg, Fla.

``Because it is the first practical approach to extending influenza prophylaxis to children, we believe this influenza vaccine will be the next significant prevention technology to enter the American health-care system and could double the current market for influenza vaccines,'' said Read.

``In the current managed-care environment, we expect that a simple, cost-effective intranasal vaccine targeting a disease that results in annual treatment costs of over $8 billion will be well received.''

Known as a ``cold-adapted influenza virus vaccine'' because it has been adapted to grow and trigger antibodies in the nasal passages, which are cooler than normal body temperature, the vaccine was first developed in the 1960s by Dr. H.F. ``John'' Maassab, chairman of the Department of Epidemiology at the University of Michigan and a member of Aviron's scientific advisory board.

The first human clinical trials of the vaccine were conducted in 1975. Unlike conventional influenza vaccines -- which consist of partially purified killed (inactivated) influenza viruses -- the cold-adapted virus is a modified living virus that is administered intranasally rather than by injection.

The vaccine, which combines the core of a harmless flu virus with the coat of a virulent strain, triggers stronger, longer-lasting local immune protection than does the conventional killed-virus vaccine.

``It has been shown that the cold-adapted bivalent influenza vaccine is safe, immunogenic and at least as effective as the inactivated vaccine in preventing culture-confirmed influenza virus illness,'' said John R. LaMontagne, Ph.D., director of the Division of Microbiology and Infectious Diseases, NIAID.

Aviron will conduct Phase I/II clinical trials in adults and children in 1995 and will begin Phase III field trials in the winter flu seasons of 1996-97 and 1997-98. Under the CRADA, the NIH (NIAID) will continue to support the project by enrolling subjects in its network of vaccine technology evaluation units (VTEUs).

These trials will be used to support FDA approval of a trivalent preparation (the current inactivated influenza shot is also trivalent -- formulated using three currently circulating strains).

Just as the current injectable vaccine is updated by the Centers for Disease Control and the FDA in response to worldwide surveillance, the harmless virus that comprises the core of the cold-adapted vaccine can be ``retrofitted'' with an outer covering that matches the new epidemic strains.

Because the vaccine will be delivered as a simple nasal spray, it provides the first practical way to immunize children on an annual basis. This is important, because while most mortality from the annual influenza epidemic (averaging 20,000 deaths in the United States each year) is in the elderly, most of the morbidity and illness occurs in young children, who are thought to facilitate the spread of the disease in the household and throughout the general population.

The vaccine will be delivered directly to the site that influenza normally infects -- the nasal passages -- where it will replicate to produce a strong local immunity. Delivery will be accomplished using a novel spray syringe which releases a large particle aerosol spray. Studies have shown that other nasal spray devices work well with this vaccine, but safety and efficacy must be documented with Aviron's specific delivery technology.

``The ease of delivering this vaccine to young children leads us to believe that pediatric opinion leaders will support widespread use of this vaccine once further data are available,'' said Read.

Under the agreement with the University of Michigan, Aviron will receive an exclusive worldwide license, excluding Japan, to the technology for use of this system as a vaccine and as a vector to deliver combined vaccines or gene therapy.

The CRADA with NIAID (NIH) provides for joint contributions by Aviron and NIH to clinical trials and exclusive commercial rights to data generated by all previous clinical trials. Though the precise nature of the financial arrangements remains confidential, Aviron's two new agreements attempt to balance a mix of immediate consideration in the form of cash and equity with a relatively low royalty rate.

This will give the company flexibility to price the vaccine according to its cost effectiveness within the global health-care delivery market. Aviron expects to spend more than $20 million of its own funds in support of clinical trials, scale-up manufacturing and regulatory filings.

Aviron is an emerging biopharmaceutical company whose strategy is to focus on the prevention of disease. The company's goal is to develop live vaccine products to prevent a wide range of viral infections that affect the general population, providing a cost-effective means of addressing a number of major diseases.

Aviron was founded by J. Leighton Read, co-founder of Affymax, and three leading university scientists: Peter Palese, Ph.D., The Mount Sinai School of Medicine; Bernard Roizman, Sc.D., University of Chicago; and Richard Whitley, M.D., University of Alabama School of Medicine.

The company is developing vaccines against respiratory syncytial virus, cytomegalovirus, varicella zoster virus and is currently in preclinical trial with its herpes simplex virus and genetically engineered influenza vaccine candidates.

CONTACT: Aviron, Burlingame

J. Leighton Read, 415/696-9100

or

Keatinge & Associates Inc.

Richard W. Keatinge, 619/625-2100