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Amid pressure to vaccinate civilians at risk for anthrax, evidence has
emerged that unauthorized changes in the vaccine manufacturing process
before the Gulf War may have radically boosted the potency of the
controversial shots.
Veterans groups and armed services personnel have complained that the
anthrax vaccine is unsafe, and they say the new evidence lends credence to
their view.
Researchers at the Army's biological warfare defense lab found as much
as a 100-fold increase in the concentration of the anthrax vaccine's active
ingredient in batches produced after a switch to new filters in 1990.
The previously unpublished report was uncovered by investigators of the
General Accounting Office, which has been studying the complaints from
veterans and military personnel. The GAO released its findings last week.
"Somebody ought to look at this question as we go forward to
approve this vaccine," said Nancy Kingsbury, managing director for
applied research at the GAO.
The national Centers for Disease Control and Prevention has recommended
that 800 lab technicians who are processing suspected anthrax samples
receive the vaccine. It is also considering a recommendation that postal
employees who work near high-speed sorting machines receive the vaccine.
RISKS NOT UNDERSTOOD
Whether higher concentrations of the active ingredient could be harmful
is still unknown, investigators say. The active ingredient, known as
protective antigens, are particles from a dead anthrax bacteria that are
used to stimulate the immune system to produce antibodies. Although the
antigens train the body's immune system to attack anthrax bacteria, there
can be too many of them.
"Overstimulation of the immune system in certain respects can lead
to immunological disorders," said Dr. Jack Melling, formerly head of
Britain's anthrax vaccine program and a consultant to the GAO.
Vaccine critics said the report bolsters suspicions by veterans that the
anthrax vaccine they took in 1990 is somehow related to Gulf War Syndrome,
the symptoms of which include chronic pain, skin rashes, nausea, memory
loss and concentration problems.
OPPOSITION TO VACCINES
Current efforts by the Pentagon to vaccinate 2.4 million military
personnel have run into stubborn opposition by soldiers, sailors and airmen
who maintain that a disproportionate number of those taking the shots have
suffered dangerous side effects.
Army Spc. Sandra Larson of Spokane died of aplastic anemia after taking
the sixth shot in the series that makes up the vaccine. Last week, her
family filed suit against vaccine maker Bioport Corp., of Lansing, Mich.,
alleging that the vaccine is at fault.
The company maintains that the vaccine is no more dangerous than
childhood vaccines used against diphtheria and whooping cough.
PRODUCED BY PRIVATE FIRM
Bioport is a private company that acquired rights to anthrax vaccine
manufacturing in 1998 from Michigan Department of Public Health, which had
been making it since 1970. Until the Gulf War, it was used primarily by
laboratory workers and veterinarians who might be exposed to the rare
disease.
Kingsbury's report, delivered to the House national security
subcommittee last week, also describes how the Michigan Department of
Public Health, under contract with the Pentagon, changed both the reactor
vessels in which the vaccine is made and the filters with which it is
refined -- without FDA approval.
In fact, the U.S. Food and Drug Administration knew nothing about the
switch from ceramic to nylon filters -- which boosted production in 1990 --
until GAO investigators informed the agency in December 2000. The changes,
including two subsequent switches of nylon filters in 1996 and 1997, were
approved after the fact by the FDA only last July.
"This conforms with what we have seen in the past, that the
producers played pretty fast and loose with the recipe," said Lawrence
Halloran, counsel to the national security subcommittee chaired by Rep.
Christopher Shays, R- Conn.
FDA SAYS VACCINE IS CONSISTENT
Despite concerns raised by the GAO, the FDA contends that nearly a
decade of records show the vaccine composition has been consistent.
"The FDA reviewed all potency data results from pre-1990 through 1998
and detected no changes in potency testing results throughout the time
period in which filters were changed," said FDA spokeswoman Lenore
Gelb.
At the same time, the FDA has forbidden Bioport from shipping its
vaccine since 1998, citing a variety of quality control problems.
Kim Brennen Root, spokeswoman for Bioport, said yesterday that the
vaccine is safe. "The GAO continues to spend time and resources
looking for a smoking gun. There is no smoking gun," she said.
But Russell Dingle, an American Airlines pilot who resigned from the
Connecticut Air National Guard rather than take required anthrax shots,
said the GAO report underscores how a succession of anthrax vaccine makers
flouted rules designed to assure safe medicines.
"The military had determined in 1991 that the changes they had made
increased the potency 100-fold. The FDA did not know about it until we told
them," Dingle said.
The GAO turned the 1990 Army study over to the FDA last week. "We
are reviewing it," said the FDA's Gelb.
CONCENTRATION VARIES
A copy of the document obtained by The Chronicle shows that the
concentration of protective antigen varied substantially among the 19
batches studied by scientists at USAMRIID, the Army biological warfare
defense lab at Fort Detrick, Md.
The highest concentration of active ingredient recorded in a batch
before the change in filters was 20.6 micrograms per milliliter. That is
nearly 100 times the lowest level in the series, 0.23 micrograms per
milliliter, using the older filter.
USAMRIID could not be reached for comment. However, in Kingsbury's report
to Congress, she acknowledges that they explained that the results of their
work "should be interpreted cautiously," because the testing
method used at the time was new -- although it is widely accepted today.
Lt. Col. John Gravenstein, deputy director of the Pentagon's Anthrax
Vaccine Immunization Program, said service personnel should be reassured
that the shots are safe. "The nation's best biological scientists are
at the FDA, not the GAO," he said.
ANTHRAX PROTECTION
Veterinarians, livestock handlers, wool mill workers, anthrax
researchers and military personnel are vaccinated for anthrax. Immunization
is achieved with six shots over a period of 18 months. Then an annual
booster shot is needed. .
A combination of three toxic antigens makes anthrax lethal. One of them,
Factor II, the "protective" antigen, is used in the vaccine
because it is the necessary link that makes the combination lethal.
.
-- The vaccine
The vaccine is made from a strain of anthrax that does not cause the
disease but does produce protective antigens. The vaccine contains no whole
bacteria, dead or alive.
-- How it works When the vaccine is injected, the Factor II antigen is
taken up by white blood cells, which use it to create antibodies.
-- Protection
The immune system now stores copies of the antibody, so the body is
ready if it comes into contact with anthrax.
.
-- Vaccine makeup
The vaccine is called Anthrax Vaccine Adsorbed because the active
ingredient, Factor II antigen, is adsorbed, or attached to aluminum hydroxide
particles, to be more easily taken up by the body. Water makes up 99% of
the vaccine, along with trace amounts of preservatives. .
Factor I antigen
With Factor II creates fluid buildup and swelling .
Factor III antigen
With Factor II produces some lethal effects .
Factor II antigen
When combined with both Factor I and Factor III, an overwhelmingly
lethal toxin is formed.. .
Sources: Bioport; Department of Defense; Reuters; New York Times
John Blanchard / The Chronicle
E-mail Sabin Russell at srussell@sfchronicle.com.
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