Vaccine Update: New Avian Strain, FDA Guidelines, and Clinical Funding

Development Begins on Mutated H5N1 Virus Vaccine

Following an announcement of the emergence of a mutated strain of the deadly H5N1 virus, this week, Health and Human Services Secretary Michael Leavitt authorized the National Institutes of Health (NIH, Bethesda, MD, www.nih.gov) and the Centers for Disease Control (CDC, Atlanta, GA, www.cdc.gov) to begin developing a new vaccine. This vaccine will be produced from the newly identified and isolated mutated strain from Indonesia.

After the production of pilot lots, NIH will perform clinical testing of the vaccine similar to that of the first H5N1 vaccine. “We will continue this approach as different versions of H5N1 virus or other viruses with pandemic potential appear,” said Leavitt.

So far, eight million doses of the first NIH-developed vaccine have been produced for the Strategic National Stockpile and are undergoing clinical trials. But this vaccine is based on a strain that was found in a patient from Vietnam and is effective only for the virus currently circulating in Thailand and Vietnam. It would be ineffective against the mutated H5N1 strain now circulating in Europe, Africa, and parts of Asia.

Reuben Donis, one of the researchers who isolated the new strain, explained in a CNN report that there are “at least” two groups of the H5N1 virus, the Indonesia- and Vietnam-originating strains, and “there may also be a couple of other groups.”

“It is probable that H5N1 will continue to evolve, producing even more viruses with pandemic potential and making it necessary to develop a series of vaccines,” said Leavitt in a statement given at the CDC’s 40th National Immunization Conference in Atlanta, Georgia, this week. “There is simply no way to predict which strain, if any, might produce a virus capable of mass human-to-human transmission.”

FDA drafts new guidelines to facilitate influenza vaccine development

The US Food and Drug Administration (Rockville, MD, www.fda.gov) this week issued two draft guidance documents outlining the clinical data needed to support the licensure of pandemic influenza vaccines and seasonal (trivalent) inactivated influenza vaccines.

According to FDA, the guidance documents describe the process for rapidly changing from currently licensed seasonal vaccines to new pandemic vaccines by supplementing the existing license. The agency also describes pathways toward traditional and accelerated approval of new vaccines. The approaches apply not only to split-virus and whole-virus inactivated vaccines (trivalent and pandemic), but also address new technologies such as cell culture and recombinant development and the application of adjuvants.

The draft guidances do not address the nonclinical or early clinical development of investigational vaccines nor the chemistry, manufacturing, control, or inspection of the manufacturing facility needed for licensure.

Bharat Biotech to fund South Asian clinical trials for Novavax vaccine

Bharat Biotech International (BBIL, Hyderabad, India, www.bharatbiotech.com) agreed to fully fund the preclinical and clinical studies supporting the development of an H5N1 influenza vaccine by Novavax (Malvern, PA, www.novavax.com) for market in India and South Asia. Vaccines to protect against other strains of avian influenza also will be investigated. The strategic alliance makes BBIL responsible for the sale and distribution of the vaccine in these markets and provides Novavax unrestricted access to all preclinical and clinical data generated by BBIL.

Novavax will apply its recombinant DNA technology to produce virus-like particle vaccines of antigenic structures, which mimic a virus to produce an immune response, as well its “Novasome” adjuvant technology for vaccine development.