Analysis:Protein Sciences Fast on Flu Shot

By STEVE MITCHELL

Protein Sciences said Thursday it has developed a commercially viable cell-based method for producing influenza vaccines against potential pandemic strains, such as the deadly bird flu, that takes only weeks instead of the several months required for traditional egg-based vaccines.

However, some experts cautioned that the new treatment could be years away from approval.

The vaccine, known as FluBlok, has received accelerated approval status from the Food and Drug Administration and the company said it anticipates having the product on the market by the Fall or 2007 at the latest.

FluBlok is going to revolutionize the vaccine field and we can’t wait to get it approved, Dan Adams, Protein Sciences’ president and chief executive officer, told United Press International.

We could shortly be on the market with this product, Adams said. We’re shooting for this Fall, but we’re pretty comfortable with 2007.

But health officials weren’t so sure.

It will still be likely years away from getting it in people’s arms, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told UPI. They have it in phase 1 and 2 trials, but its a long way to getting something approved by the FDA, Fauci said.

I don’t say that in a negative way, he added. This is a promising new approach but I don’t think it’s going to solve our problems for next year.

Although there are other cell-based vaccines in development, Fauci said it’s much more likely that public health measures, such as isolation and quarantining, will be used if a pandemic strikes in the next year or so.

Despite this assessment, Adams said Protein Sciences has contracted with a very large company in Europe he would not identify to manufacture the vaccine in anticipation of a launch this fall.

Protein Sciences also has signed a letter of intent for the capacity to produce 6 million vaccine doses per week.

The plan is to tap into the annual flu shot market, which would enable them to be prepared to manufacture mass quantities in the event of a pandemic, Adams said. The cost of the vaccine would be comparable to vaccines currently produced using the egg-based method.

I think we’ll be the dominant supplier, he said. Show me another product that works better in the elderly, he added.

In a clinical study conducted last year that involved 460 people, everybody who received FluBlok was protected and did not contract the flu, he said. Based on that study, he said, FDA awarded FluBlok accelerated approval.

Adams noted that the company produced a vaccine for bird flu two years ago and stockpiled it for employees for emergency use. We offered it to the government free of charge and they never responded, he said.

Protein Sciences uses a novel approach to generate the vaccine that involves a virus, known as baculovirus, that normally infects insect cells. The genes responsible for producing the hemagglutinin protein found on the surface of influenza viruses are extracted and then inserted into a baculovirus.

Insect cells are then infected with the baculovirus, which induces them to produce recombinant hemagglutinin protein. This protein is then purified and incorporated into the vaccine.

In addition to speed, the advantages of this production method are that the proteins used in the resulting vaccine will always match currently circulating flu viruses, Adams said.

Starting from a stocked recombinant baculovirus bank, a closely matched vaccine can be massively produced within 2 weeks, said Keyang Wang, a scientist at Protein Sciences who presented research on the vaccine Thursday at the American Society for Microbiology Biodefense Research meeting in Washington.

Wang’s research team reported that they used this production method to successfully generate four different types of hemagglutinin proteins –H5, H7, H9 and H2– that could potentially lead to pandemics in the future.

It has been suggested that the next pandemic strain may be derived from H5, H7, H9 or H2 influenza viruses, Wang said. The preparation of the recombinant baculoviruses for the production of these antigens and the successful purifications gives us a great advantage in fighting against a potential influenza pandemic, if it derived from any of these strains.