By Maggie Fox
WASHINGTON (Reuters) - A small biotechnology company trying to develop needle-free vaccines won a boost to its efforts on Tuesday with U.S. government approval to test a bird flu skin patch on more people.
Iomai's patch is not a vaccine, but rather delivers what is called an adjuvant -- an immune boosting agent that will be delivered along with a vaccine to try to make it work better.
The vote of confidence from the Health and Human Services Department adds impetus to all of the company's projects.
"The Iomai immunostimulant patch has the potential to change how we react to an influenza pandemic, and we will move ahead quickly with the development of this technology," Stanley Erck, president and chief executive officer of Iomai, said in a statement.
HHS, which gave Iomai $128 million to work on the patch last year, said the company could do a phase 2 safety trial -- typically involving a few dozen people to see if a product is safe and whether there is any indication it works.
If a phase 2 trial succeeds, companies can move to phase 3 studies, which are carefully designed to prove a product has the intended effect and are needed for final approval by the U.S. Food and Drug Administration.
Last month, the company reported the skin patch helped boost a bird flu vaccine so well that people appear to be protected by a single dose.
This could help stretch vaccine supply during a pandemic.
Often, adjuvants are mixed right in with a vaccine but Dr. Anthony Fauci of the National Institute for Allergy and Infectious Diseases said there is reason to believe a patch may work better.
"Right beneath the skin are a group of cells called Langerhans cells," Fauci said in a telephone interview.
"When you put the patch on the skin, they take up the adjuvant and go directly to the lymph nodes. The thought is that ... you will get a more robust response."
Current approved vaccines against the H5N1 avian influenza virus require two doses to be fully effective.
The patch, applied after gently scraping the skin with a light, sandpaper-like device, is being used to boost an H5N1 vaccine made by the Belgian drug company Solvay.
The H5N1 avian flu virus is sweeping through flocks of poultry in Asia and sometimes Africa and Europe. It has infected 380 people in 14 countries and killed 240 of them since 2003.
The fear is that the virus might change just enough to pass easily from one person to another, sparking a deadly pandemic.
At least 16 companies are testing H5N1 vaccines. But global flu vaccine production capabilities are limited and if larger doses are needed, fewer people could be vaccinated in a pandemic.
Iomai is also working to use its needle-free technology to make vaccines against anthrax, seasonal influenza and traveler's diarrhea.
Last week, it won a grant of up to $943,856 from the U.S. Army Medical Research and Materiel Command to do preclinical work on a patch-based version of the anthrax vaccine.
The current anthrax vaccine licensed in the United States is given in six different injections over 18 months and must be refrigerated.