New DNA Vaccine Proves to be Effective Against Avian Flu

Author: Drucilla Dyess

Vical Incorporated has announced that a newly developed DNA-based vaccine for the H5N1 avian flu has shown to safely stimulate the immune system and protect against flu in their preliminary trials. Vical researches and develops biopharmaceutical products based on its patented DNA delivery technologies for the prevention and treatment of serious or life-threatening diseases.

The trial consisted of two injections given at days 0 and 21 to 100 study volunteers, aged 18 to 45. Of those who received the higher dose, 67 percent had immune responses allowing for protection against becoming infected with the H5N1 avian flu virus with no serious adverse reactions. The authors of the study wrote, "These results suggest that one strategy for pandemic control could involve prevaccination of some segments of the population prior to the emergence of a pandemic so that effective protection could be achieved with a single dose schedule if and when a pandemic emerges." The study is published in the August 1 issue of The Journal of Infectious Diseases, now available online.

The Phase I clinical trial is being conducted to demonstrate the safety of the vaccine and will continue. In a statement, Dr Robert Belshe of Saint Louis University School of Medicine, who monitored safety, said in a statement, "The preliminary results from this Phase 1 trial indicate for the first time that DNA vaccination against H5N1 influenza is well-tolerated and can induce impressive antibody responses." He went on to explain, "Successful development of a safe and effective DNA vaccine will help address the potential public health threat of pandemic influenza."

Unlike conventional vaccines that use bits of the actual virus grown in chicken eggs and take four to six months to develop and manufacture, DNA-based vaccines can be made in six to eight weeks, which would be a time-saving advantage when responding to a pandemic outbreak. DNA vaccines use bits of genetic material (plasmids) to create an immune response against a specific part of the virus. These vaccines are made to last longer than standard vaccines in conditions of both heat and cold.

There are at least 16 companies working to create vaccines against H5N1 influenza. According to statement from Vijay Samant, Vical's president and chief executive, "The ability to manufacture DNA vaccines in weeks rather than the months required for conventional vaccines may provide a significant advantage when dealing with an emerging infectious disease such as pandemic influenza."

The H5N1 avian flu is now deep-rooted amid birds in Asia, parts of Europe, Africa, and the Middle East. Half a billion birds have died or been culled to prevent the spread of the disease. According to the World Health Organization, the virus has cost the lives of 243 out of 385 people in 15 countries, although the virus is rare among humans.

The fear is that the as the virus mutates, it could change into a form that could easily spread from person to person creating a global pandemic nightmare that could take the lives of millions of people.