April 5, 2006
Avian Flu Vaccine and Drug Preparedness 2006 Update
March 29, 2006
The Food and Drug Administration approved Relenza (zanamivir) for prevention of influenza A and B in adults and in children above the age of five. In several trials Relenza was shown to significantly reduce the development of symptoms in households where flu was present. The side effects noted during the study were fairly mild in both children and adults; however some severe side effects were noted. Of note, Relenza is not recommended for use by individuals with respiratory problems, including asthma. This drug is being added to the Strategic National stockpile to prepare for a flu pandemic.
The National Institutes of Health and the National Institute of Allergy and Infectious Diseases released the results of the first H5N1 vaccine trials in healthy adults. About half (54%) of the individuals made virus-neutralizing antibodies to the H5N1 virus after two shots of the highest dose (90ug) of the vaccine. This trial had two parts. The initial part consisted of four trial groups and one control group, each of which received a different amount of vaccine (7.5, 15, 45, and 90ug). One month after vaccination the individuals were tested for antibody levels. The groups then received a second vaccination, followed by antibody testing one month later. After this initial trial proceeded without any complications a larger trial was preformed using the same protocols. In general, the complications noted from vaccination were mild and the vaccine was well tolerated. This vaccine was produced by Sanofi Pasteur, in Pennsylvania, and was prepared from an H5N1 strain isolated in Southeast Asia during 2004. The March 30, 2006 issues of the New England Journal of Medicine contained the complete publication of the study.
March 26, 2006
Sequence information on the second clade of H5N1 was released. The sample was isolated from a patient in Indonesia. Antigenic differences between clade 1 and clade 2 are significant enough to require the production of separate vaccines for the two clades. The same March 30th issue of the New England Journal of Medicine also included a case report of a woman I Anhui province in China who during her pregnancy was infected with this clade 2 of H5N1, and died. An accompanying editorial noted that even with vaccination against clade 1 of H5N1 this patient would likely not have been protected against her clade 2 H5N1 infection.
March 22, 2006
The Department of Health and Human Services has ordered 2.2 million more treatment courses of the antiviral drug Relenza from GlaxoSmithKline and 3.8 million more treatment courses of Tamiflu from Roche. These treatments will be added to the Strategic National Stockpile. This brings the total number treatment courses to 26 million. The goal of the Strategic National Stockpile is to purchase enough antiviral drugs for 25% of the United States population. This would total 75 million courses with an additional 6 million courses for initial immediate containment effort sin the USA, thus totaling 81 million courses by 2008.
March 2, 2006
The Food and Drug Administration has started an initiative to expedite the development of seasonal and pandemic flu vaccine. To do this the FDA provided guidelines for the submission of clinical data that shows efficacy and safety. This fast track approval process was used to approve last year’s flu vaccine, Fluarix. By doing this, the FDA is trying to provide vaccine developers with ways to quickly create safe and effective vaccines for both seasonal and pandemic flu in an effort to better protect the U.S. This work is in parallel with new guidance from the FDA for the development of cell culture technology will be essential for the production of large amounts of influenza vaccine.
The World Health Organization released a new vaccine strain made available for vaccine development. In October 2005 the WHO Global Influenza Programme reported that a significant enough number of changes had occurred in the haemagglutinin genes to warrant the changing of the vaccine strain. The new circulating strains were found to be genetically distinguishable from the previous vaccine strain chosen in 2004. This new strain is available from both the Centers for Disease Control and Prevention and the WHO and is know as the A/Indonesia/5/2005 strain of H5N1 influenza. The sequence of the haemagglutinin and neuraminidase genes is available from Los Alamos National Laboratory database. This information can be distributed to companies for vaccine development.
February 3, 2006
The Food and Drug Administration approved a new laboratory test to detect human infections with avian influenza A/H5 viruses. This test was developed by the CDC to diagnose H5 strains of influenza in patients. The product is known as the Influenza A/H5 (Asian lineage) Virus Real-time RT-PCR Primer and Probe Set. This new test can provide preliminary confirmation of H5 viruses in about four hours, while the previous tests required two to three days for results. This test has been distributed to about 140 labs that are part of the Laboratory Response Network, and are currently in all fifty states. The CDC has been working with the WHO to share this technology with centers around the world that are performing H5 influenza testing.
Jennifer Harris and James Sidas
Graduate Students, Georgetown Master of Science Program in Biohazardous Threat Agents and Emerging Infectious Diseases. MICB-524 course: “Emerging Infectious Diseases: The Past as Prologue”.
Edited by: Daniel R. Lucey, MD, MPH. MICB-524 Instructor. Director, Center for Biologic Counterterrorism and Emerging Diseases. EROne Institutes, Washington Hospital Center, Washington DC.