FDA Develops Alternative Assay to Increase Availability of Influenza Vaccines - Pharmaceutical Technology

Latest Issue
PharmTech

Latest Issue
PharmTech Europe

FDA Develops Alternative Assay to Increase Availability of Influenza Vaccines



A laboratory assay developed by scientists at FDA could speed the release of pandemic influenza vaccines to the public by shortening the time it takes to test vaccine potency. The FDA scientists developed the new assay in response to the recommendation of a workshop organized by the World Health Organization (WHO) following the 2009 H1N1 influenza pandemic and aninitiative by the US Department of Health and Human Services’ Biomedical Advanced Research and Development Authority (BARDA).

One advantage of the new potency assay is that it does not require the use of antisera for testing influenza vaccines. The current standard potency assay for influenza vaccines uses antibodies against hemagglutinin (HA), a protein on the surface of the virus that is an important component of influenza vaccines. In order to make the antibodies, vaccine viruses aretreated with enzymes to release HA proteins from their surface. If the anti-HA antibodies recognize and bind to the HA, the two molecules form tiny visible rings, demonstrating that the HA is suitable for use in influenza vaccines.Drawbacks to the current assay are that the use of enzymes to release HA from influenza viruses does not reliably produce sufficient amounts of HA and the resulting proteins are difficult to purify before injecting into sheep. The new assay does not use antibodies that attach to HA, instead it is based on thenatural interaction between the influenza virus envelope protein, HA, and the receptor molecule on the surface of target cells lining the human respiratory tract.

The FDA researchers used artificial versions of the HAreceptors known to be targeted by human influenza, and tested whether the HA proteins from influenza vaccines recognized and attached to them. Only those HA proteins that were identical to the viral protein, and thus able to act as a vaccine, were able to fit into the appropriate SA-glycan receptor sites. The scientists used a surface plasmonresonance technique to measure the amount of HA proteins attached to the artificial receptors that were coated on special chips. This allowed them to determine how much HA was in vaccine samples, as well as the stability of those proteins. This assay was also able to measure the amount of HA protein in vaccines that were mixed with adjuvants. Overall, the SPR-based assay measurements of HA content in vaccines agreed closely with those obtained by the standard antibody-based ring-forming assay. This suggests that the newer assay might be reliable enough to replace the slower, standard assay.

Source: FDA

ADVERTISEMENT

blog comments powered by Disqus
LCGC E-mail Newsletters

Subscribe: Click to learn more about the newsletter
| Weekly
| Monthly
|Monthly
| Weekly

Survey
What role should the US government play in the current Ebola outbreak?
Finance development of drugs to treat/prevent disease.
Oversee medical treatment of patients in the US.
Provide treatment for patients globally.
All of the above.
No government involvement in patient treatment or drug development.
Finance development of drugs to treat/prevent disease.
28%
Oversee medical treatment of patients in the US.
9%
Provide treatment for patients globally.
9%
All of the above.
41%
No government involvement in patient treatment or drug development.
13%
Jim Miller Outsourcing Outlook Jim MillerCMO Industry Thins Out
Cynthia Challener, PhD Ingredients Insider Cynthia ChallenerFluorination Remains Key Challenge in API Synthesis
Marilyn E. Morris Guest EditorialMarilyn E. MorrisBolstering Graduate Education and Research Programs
Jill Wechsler Regulatory Watch Jill Wechsler Biopharma Manufacturers Respond to Ebola Crisis
Sean Milmo European Regulatory WatchSean MilmoHarmonizing Marketing Approval of Generic Drugs in Europe
FDA Reorganization to Promote Drug Quality
FDA Readies Quality Metrics Measures
New FDA Team to Spur Modern Drug Manufacturing
From Generics to Supergenerics
CMOs and the Track-and-Trace Race: Are You Engaged Yet?

Click here