Background Analysis: US FDA Advisory Committee to Make Recommendations on Strains for Influenza Virus Vaccine – MAR 1, 2018 (VRBPAC)

Announcement

The US FDA has scheduled a Vaccines and Related Biological Products Advisory Committee (VRBPAC) meeting for Thursday, March 1, 2018 to discuss and make recommendations on the selection of strains to be included in the influenza virus vaccines for the 2018-2019 US influenza season and to hear an overview of the research program in the Laboratory of Mucosal Pathogens and Cellular Immunology (LMPCI), Division of Bacterial, Parasitic and Allergenic Products (DBPAP), Office of Vaccines Research and Review (OVRR), Center for Biologics Evaluation and Research (CBER), FDA.

Indication Background

Description of Indication

Influenza is a contagious respiratory illness caused by influenza viruses that infect the respiratory tract. It can cause mild to severe illness, and at times can lead to death. Seasonal influenza is characterized by a sudden onset of high fever, dry cough, headache, sore throat, muscle and joint pain, and severe malaise.

Most people recover within a week without requiring medical attention. However, some people, including older people, young children, and people with certain health conditions, such as chronic heart, lung, kidney, liver, blood or metabolic diseases or weakened immune systems, are at high risk for serious flu complications. Influenza virus infections can cause primary influenza viral pneumonia; exacerbate underlying medical conditions (e.g., pulmonary or cardiac disease); lead to secondary bacterial pneumonia, sinusitis, or otitis media; or contribute to co-infections with other viral or bacterial pathogens. In the US, on average, 5% to 20% of the population gets the flu, and more than 200,000 people are hospitalized from seasonal flu-related complications annually.

There are three types of influenza viruses: A, B and C. Type C infections cause a mild respiratory illness and are not thought to cause epidemics: Human influenza A and B viruses cause seasonal epidemics of disease.

In temperate climates, seasonal epidemics occur mainly during winter months. In the Northern Hemisphere, the flu season can begin as early as October and can last as late as April or May. In the temperate regions of the Southern Hemisphere, influenza activity typically occurs during April – September.

Influenza A viruses are divided into subtypes based on two proteins on the surface of the virus: the hemagglutinin (H) and the neuraminidase (N). There are 17 different hemagglutinin subtypes and 10 different neuraminidase subtypes. Influenza A viruses can be further broken down into different strains. Influenza B viruses are not divided into subtypes, but can be further broken down into different strains. Changes in influenza viruses occur in two ways: antigenic drift, small changes that happen continually over time; and antigenic shift, which is an occasional, abrupt, major change in influenza A viruses, resulting in new hemagglutinin and/or new hemagglutinin and neuraminidase proteins. Type A viruses undergo both kinds of changes; influenza type B viruses change only by the more gradual process of antigenic drift.

Product Background

The following injectable vaccines are FDA-approved:

    AFLURIA by Seqirus Pty. Ltd.

    Agriflu by Novartis Vaccines and Diagnostics, Inc.

    FluLaval by ID Biomedical Corporation of Quebec

    Fluarix by GlaxoSmithKline Biologicals

    Flublok by Protein Sciences Corporation

    Flucelvax by Seqirus, Inc.

    Fluvirin by Seqirus Vaccines Limited

    Fluzone by Sanofi Pasteur, Inc., which also available for intradermal administration

    Fluad (adjuvanted) by Seqirus, Inc

An intranasal vaccine, called FluMist, by Medimmune, LLC, is also FDA-approved.

Regulatory Background

The viruses to be included in the vaccine can change each year, based on international surveillance and scientists’ estimations about which types and strains of viruses will circulate in a given year. Each year, the FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) meets to select the influenza viruses for the composition of the influenza vaccine for the next US influenza season. During this meeting, the Advisory Committee reviews and evaluates the surveillance data related to epidemiology and antigenic characteristics of recent influenza isolates, serological responses to previous vaccines, and the availability of candidate strains and reagents. In the past, the Committee made recommendations of two A strains, usually A/H1N1, A/H3N2, and one B strain, to be included in a trivalent vaccine. More recently, they have also voted on an additional B strain to be included in a quadrivalent vaccine.

During the current flu season (2017-2018 flu season) the media has reported extensively on the suboptimal protection of the H3N2 strain that was chosen, namely the A/Hong Kong/4801/2014 (H3N2)-like virus. On February 13, 2018, the FDA Commissioner, Dr. Scott Gottlieb, stated in two tweets “#FDA plays an important role in protecting public health by working with partners to select strains for the annual #flu vaccine based on best scientific predictions of the strains most likely to hit next season.” “The just announced March 1 meeting of the Vaccines & Related Biological Products Advisory Committee (VRBPAC) will use lessons learned this year to make recommendations on selection of strains to be included in flu vaccines for 2018-2019.” On the day prior, he tweeted, “There are several potential reasons why we may be seeing less than optimal protection from this year's vaccine that are being investigated. We're actively working on elucidating the causes with colleagues at @CDCFlu and we'll communicate this week as we have more information.” @CDCFlu is the twitter handle for the US Centers for Disease Control and Prevention.

What’s Next?

Tarius will send a Briefing Summary after briefing materials are posted to FDA’s website (typically within 2 days of the meeting). This report will provide a summary of the FDA and the Sponsor’s briefing materials.

Tarius will send a Results Wire soon after the meeting. This report will include the voting outcomes, if applicable, and key outcomes of the discussion.

METADATA: Sponsor: none Drug Name: none Drug Class: vaccine Indication: influenza

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DISCLAIMER: The information in this document is for informational purposes only. The SAC Tracker Background Analysis contains information from publicly available sources, including FDA, sponsor, scientific, and clinical websites. Tarius A/S assumes no liability for any inaccurate or incomplete information, or for any actions taken in reliance thereon. © Tarius A/S. All rights reserved.