U.S., Canada Partner to Obtain Licensed Stockpile of Smallpox Vaccine
By Gerry J. Gilmore
American Forces Press Service
WASHINGTON, April 30, 2002 DoD scientists and contractors are working to obtain U.S. Food and Drug Administration approval for a smallpox vaccine developed by the military a decade ago, according to an Army medical researcher at Fort Detrick, Md.
However, it will likely take a few years of testing until the FDA approves the vaccine for licensure and renewed production, said Army Col. David L. Danley, project manager for the Joint Vaccine Acquisition Program. He noted that an agreement signed March 27 by DoD and Canada's Department of National Defence will facilitate that goal.
Danley, a research scientist, holds a doctorate in biological sciences, immunity and infectious diseases. He said his organization is responsible for advance development, FDA licensure, and management of biological defense vaccines for the DoD.
The U.S.-Canada agreement, he explained, "ensures that we will produce a vaccine that is licensed in both the United States and Canada" that can be shared between the two countries and used by our armed forces.
"This is both a DoD and a national concern. There are no potential bioterror weapons that are as communicable or infectious as smallpox," he said.
He said the DoD smallpox vaccine under development was created at the U.S. Army Medical Research Institute of Infectious Diseases at Detrick in the early 1990s. "But there was no requirement at that time to make a licensed smallpox vaccine," he noted.
While authorities seek FDA approval, Canadian defense officials will work to have the vaccine licensed by their counterpart government agency, Health Canada, DoD officials have said.
The U.S.-Canada agreement uses a structured process to obtain licensure and to set up production of approved vaccine, Danley said. He added that the contractor uses "acquisition processes you'd use to build a tank" in looking for manufacturers to make and test the vaccine.
The unit cost of the vaccine probably won't be influenced by the agreement, but its availability will be improved, he said. Canada and the United States will be able to share military smallpox vaccine stockpiles, he said, as production of the new, approved vaccine picks up.
However, he said, the U.S.-Canada agreement should reduce the cost of developing the vaccine. The U.S. military, Danley noted, is working with Dynport Vaccine Co., a prime contractor in Frederick, Md., that is developing new DoD biodefense vaccines, except the currently licensed anthrax vaccine.
He said DoD is working with the Department of Health and Human Services to ensure availability of current smallpox vaccine and antiserum stockpiles for military use. HHS has a contractor that's also making a new vaccine to support the civilian population.
Smallpox vaccine uses live vaccinia virus, which is not smallpox, but a related virus, Danley said. Healthy vaccine recipients might feel short-term side effects, he noted, but there is little chance they'd become seriously ill from vaccinia.
The vaccine can be dangerous -- possibly fatal -- to patients with impaired immunity systems, he remarked. He noted, however, that the antiserum VIG, short for Vaccinia Immune Globulin, can be used to treat some adverse events associated with smallpox vaccination.
Danley noted people haven't died from smallpox in a long time. World health officials declared naturally occurring smallpox wiped out in the 1980s. The last laboratory- acquired human smallpox infection occurred in 1978 in Great Britain, he said, and the last field case of smallpox was discovered in Somalia in 1977. DoD stopped routine smallpox vaccinations in 1989-1990 at the end of the Cold War.
U.S. military concern about the disease was rekindled by the discovery that the former Soviet Union weaponized smallpox during the Cold War, he said.
The world's only smallpox virus samples were believed contained in two depositories, one in the old Soviet Union, and the other at the Centers for Disease Control in Atlanta. "There is suggestion that unfriendly Third World countries may hold smallpox samples," Danley said.
Third, he noted, the genetic code of smallpox is known. Related viruses could be genetically engineered into smallpox, he said, pointing to recent news reports about the close relationship between so-called camel pox and smallpox.
Military and other federal, local and state authorities are concerned about smallpox as a bioweapon, Danley said, noting qualities that make it dangerous to human populations: Smallpox is highly infectious and easily transmitted in the air and by contact. Symptoms can take up to two weeks to show, so the disease conceivably can spread before anyone realizes there's been an attack.
Smallpox is a debilitative disease and is fatal in about 30 percent of infections. Victims become badly and permanently scarred over their faces and bodies by pox, which are skin eruptions. Danley said the very young and very old seem the most susceptible, perhaps due to immature or weakened immune systems.
Smallpox victims generally experience "first a fever, then tiredness, until a rash appears that becomes skin eruptions," he said.
New vaccine work began during the 1980s, he added, but advanced development started in 1998. But the new smallpox vaccines "have not undergone the extensive clinical trials required to demonstrate product safety and effectiveness for FDA licensure," Danley said. Even if vaccine trials that start this summer go well, it will be 2004 or 2005 before FDA licensure could be expected, he noted.
"However, existing smallpox vaccines may be used as investigational new drugs, and can be administered to troops with informed consent," he noted. "We would have to screen recipients very carefully to ensure that we don't administer the smallpox vaccine to somebody who might become critically ill."