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Approved Swine Flu Vaccines

Details of the Four Vaccines Approved by the FDA for Swine Flu

Sep 19, 2009 Megan Doyle

Four vaccines have been approved by the FDA for the prevention of the swine flu. Descriptions of each of these vaccines and their efficacy are detailed here.

In order to prevent the swine flu epidemic from rapidly spreading this fall as cold and flu season begins, the government has contracted vaccine production from several large pharmaceutical companies. Four of these companies have produced vaccines that appear to be safe and effective against the swine flu and have recently gained FDA approval to begin mass producing and distributing the immunization across the nation.

Swine Flu Vaccine Produced By Novartis

The H1N1 flu vaccine developed by Novartis Vaccines and Diagnostics Ltd. is indicated for active immunization of people age four and older. The company recently published a preliminary safety and efficacy report in the New England Journal of Medicine. The company tested this vaccine with and without an oil-in-water adjuvant, known as MF29. Adjuvants are used in vaccines to improve the immune response so that less vaccine is needed. The researchers are reporting data from 100 volunteers who received a 7.5-microgram dose of adjuvanted vaccine. Immune responses were highest in participants that received two doses of this vaccine, but 80% of recipients exhibited responses deemed to be protective against the flu after only one dose.

Sanofi Pasteur Incorporated Receives Approval for Swine Flu Vaccine

The National Institutes of Health (NIH) recently released results from its trial of swine flu vaccines in 2,800 healthy people. Researchers from the NIH found that the H1N1 vaccine produced by Sanofi Pasteur Inc. produced a strong immune response in 96% of adults ages 18 to 64.

CSL Limited’s Vaccine Protects Against Swine Flu

CSL Limited has published data from a company-sponsored trial of its swine flu vaccine in 240 healthy volunteers. Following injection, 90% of participants achieved a strong immune response within three weeks. The NIH has also tested the swine flu vaccine made by CSL Ltd. in its trial. The NIH observed that this vaccine produces a robust immune response in 80% of adults ages 18 to 64 after 8 to 10 days, compared to 60% in adults ages 65 and older. The response seen in older adults is comparable to what is observed with the seasonal flu vaccination every year. Researchers hypothesize that this could be an acceptable response rate since elderly people are at a much lower risk of contracting the swine flu.

H1N1 Vaccine Made By MedImmune

The swine flu vaccine manufactured by MedImmune differs from the other three approved vaccines because it is distributed to recipients in the form of a nasal spray rather than an injection and is made with live, weakened swine flu virus. The immunization is indicated for use in people age two through 49 and is likely to be the first swine flu vaccine made available to the public.

Trials of all of these vaccines have shown that they can elicit a strong immune response from just one dose in just eight to 10 days. Therefore, it appears that people will only require one immunization for swine flu, allowing supplies of vaccine to cover the inoculation of a larger population. It is estimated that some supplies of these vaccines will be ready for the general public by mid October, at which time priority will given to high risk populations of people ages 18 to 64. Trial results detailing the safety and efficacy of these vaccines in children and pregnant women will be released in the near future, allowing health officials to determine the best course of action for immunizing these high risk populations.

References

Greenberg MA, et al. "Response after one dose of a monovalent 2009 influenza A (H1N1) vaccine--preliminary report." N Engl J Med. 2009.

Clark TW, et al. "Trial of influenza A (H1N1) 2009 monovalent MF59-adjuvanted vaccine-- preliminary report." N Engl J Med. 2009.

The copyright of the article Approved Swine Flu Vaccines in General Medicine is owned by Megan Doyle. Permission to republish Approved Swine Flu Vaccines in print or online must be granted by the author in writing.

Vaccines Approved to Prevent Swine Flu