THE ALIANCE
FOR HUMAN RESEARCH PROTECTION (AHRP)
142 West
End Avenue, Suite 28P
New York,
NY 10023
www.ahrp.org
FDA Docket Number 02N-0466
Comments re: Proposed smallpox vaccine trial to test the safety of Dryvax
administration to children 2 to 5 years of age
Recent public and professional
debate about smallpox vaccine and its risks provides the framework for
evaluating the ethical justification for conducting clinical trials
on children. Dryvax is a particularly impure product made of live vaccinia
virus harvested from the pustules of calves infected with (it is believed)
cowpox. Although the vaccine, which is scratched on the skin, only causes
mild infections in most people, in a small but significant number the
infection caused serious adverse reactions similar to the complications
of the disease they were designed to prevent: painful, disfiguring skin
disorders, blindness, neurological impairments and death.
Smallpox Vaccine Risks:
Smallpox vaccine is the
most highly reactive vaccine that has ever been routinely used in humans.
Routine vaccination against smallpox was terminated in about 1971 because
of severe adverse side effects from the vaccine and a low risk of exposure
to smallpox. Fever lasting for 4 to 14 days can be expected in 70 percent
of children inoculated.[1] Based
on data from a 10 state survey in 1968,[2]
the Center for Disease Control (CDC) estimates that for every 1 million
people vaccinated for the first time about 1,000 experienced reactions
that, while not life-threatening, were serious, requiring medical attention:
vaccinia rash (outbreak of sores due to accidental touching) on the
genitals or face, including the eyes, where it can damage sight or lead
to blindness; widespread vaccinia may be spread through the blood; toxic
or allergic reaction. The most recent data reveals that following vaccination,
children 1 to 4 years of age are particularly at risk of suffering from
widespread blotchy macular rashes.[3]
Furthermore, CDC estimates
that between 14 and 52 people per 1 million people vaccinated for the
first time experienced potentially life-threatening reactions. Eczema
vaccinatum: serious widespread infection with vaccinial lesions over
the body of patients with eczema or a history of eczema. Clinically,
these patients are similar to burn patients, losing fluid, serous exudate,
and electrolytes through their skin. Children < 5 have a greater risk
than other age groups-44 cases (out of one million vaccinated). Fatalities
have occurred in patients who were not themselves vaccinated, but were
close household contacts of recently vaccinated siblings etc.3 Vaccinia
necrosum (infection of skin with tissue destruction) frequently leads
to death. Finally, post-vaccinial encephalitis (inflammation of the
brain), for which there is no effective treatment and no complete recovery.
Approximately 15% to 25% of those who are stricken with post-vaccinial
encephalitis die, and 25% suffer permanent brain damage.1 No one knows
what percentage of smallpox vaccine recipients today will suffer severe
complications. But a recent study of adult primary vaccinees revealed
that 36% were sufficiently ill to miss work, school, or recreational
activities.[4]
Ethical / moral considerations:
Experts say the vaccine
can be administered 3-4 days AFTER exposure to the smallpox virus and
still "prevent or decrease the severity of clinical disease."
[5] Careful risk/benefit analysis
is, therefore, critical toward making the best decisions regarding who
should be vaccinated, and when. Adults have the right to choose whether
or not to be inoculated against smallpox--children do not have the legal
right to exercise free choice. Therefore, to meet ethical / moral standards,
those proposing the Dryvax vaccine experiment - exposing 2 to 5 year
old children to the hazards of the vaccine - must provide compelling
evidence of an imminent risk of smallpox exposure for the children sought.
Absent such evidence there is no justification for exposing children
to the severe, painful, possibly irreversible, risks of the vaccinia
virus. This is especially the case with children who are at greater
risk of severe reactions because of their lesser understanding of preventive
measures and ability to follow instructions.
Dr. Paul Offit, Chief, infectious
diseases section of Children's Hospital of Philadelphia, and a member
of the Center for Disease Control (CDC) Advisory Committee on Immunization
Practices, has seen babies who suffered adverse reactions to smallpox
vaccine. He says that in the absence of a single case of smallpox anywhere
on earth, the vaccine is too risky to use:[6]
"I would never give that
vaccine to my children because right now there is no disease out there."[7]
Don't children of less knowledgeable parents have a right to be similarly
protected from harm?
Other risks: Accidental
infection of third parties
Because vaccinia virus is
a live virus, there is the risk of its inadvertent transmission by touching
parts of the body or from contact with a vaccinated person whose lesion
is in the florid stages. Unvaccinated adults and children are at risk
of contacting the virus. Lesions of inadvertent inoculation occur most
commonly on the face, eyelid, nose, mouth, genitalia, and rectum. Lesions
in eczematous skin, in disrupted skin, and in the eye pose special hazards,
as the infection can be extensive and a threat to eyesight. [Accidental
transmission infection in other parts of resulting from the vaccine
is the most frequent complication of smallpox vaccination.3] The Dryvax
package insert states that 577 cases occurred among a million vaccinated
children aged <5 years. Furthermore, those who came in contact with
the virus were at increased risk of contacting a more severe form of
eczema vaccinatum than those vaccinated because those vaccinated were
screened out. The CDC reports that in one case, six cases of eczema
vaccinatum resulted through contact with one vaccine recipient.1 [p.11]
Some, but not all, complications
from vaccinia virus can be treated with vaccinia immune globulin (VIG),
a substance taken from the blood of previously vaccinated people. But
there is a shortage of VIG. According to the World Health Organization
"The risk of adverse events is sufficiently high that vaccination
is not warranted if there is no or little real risk of exposure. Vaccine
administration is warranted in individuals exposed to the virus or facing
a real risk of exposure. A safer vaccinia-based vaccine, produced in
cell culture is expected to become available shortly."[8]
Dryvax stockpile problems:
Dryvax, the vaccine to be
used in the proposed experiment on 2 to 5 year old children was pulled
out of storage after approximately thirty years. Dryvax stockpiles had
been freeze dried and stored in glass tubes to be mixed with a liquid
diluent just before vaccination using a bifurcated needle that allows
droplets of the vaccine to be scratched onto the skin. In 1999, the
CDC discovered that some U.S. Dryvax vaccine stockpiles had badly deteriorated:
rubber stoppers on the glass storage tubes had decayed and vacuum pressure
had been lost while the liquid diluent had changed color and there were
only one million bifurcated needles to administer more than 15 million
doses.[9] The journal, Science, reported
that one fourth of the stockpiled vials "are suspect."[10]
In the June 22, 2001 the
CDC confirmed that previous methods of vaccine production using calves
are no longer being used: "The traditional method for producing
vaccines on the scarified flank of a calf is no longer acceptable because
the product inevitably contains some microbial contaminants, however
stringent the purification measures."[11]
New vaccinia virus vaccines will be grown in laboratories using other
cell tissues such as human fibroblasts (from fetal connective tissue
cells).1 [12] CDC indicated that
new cell-culture vaccinia virus vaccine will be evaluated for safety
and efficacy by direct comparison with Dryvax using appropriate animal
models, serologic and cell-mediated immunity methods and cutaneous indicators
of successful vaccination.
In 2001, the CDC began inoculating
its staff with smallpox Dryvax vaccine, but allegedly stopped, because
the adverse reactions were greater than anticipated. The CDC has not
provided critical information from its recent experience, about the
rate of local and systemic reactions, their type and duration. Without
such up to date, current data, neither the public nor medical professionals
are able to make a reasoned risk/benefit decision about using this vaccine.
Proposed Dryvax trial on
2 to 5 year old children is unnecessary and unethical:
Not a single case of smallpox
has been reported anywhere in the world, thus the risk is, at best,
speculative. Given the history of serious adverse reactions in adults
and particularly in children, given also the complicating risk factors
of the Dryvax vaccine, it is all the more astonishing that the government
is giving its blessing to an unprecedented clinical trial in which the
smallpox vaccine will be tested in small children. To justify the exposure
of children - who are not volunteers - to the very real serious risks
associated with the smallpox vaccine, evidence must demonstrate a credible
risk to smallpox exposure for these children. If there is no evidence
of a real risk of a smallpox attack, then the experiment is wholly unethical
for it would put the children and others at risk without a potential
benefit. Indeed, the overwhelming negative response by the public and
media to the trial announcement - should preclude conducting the trial.[13]
[14]
A fundamental ethical principle
under The Nuremberg Code and federal regulations is that any experiment
in which human beings may be at risk must be justified by showing that
the information sought is "unprocurable by other methods or means."[15]
The purpose of the study, it is claimed, is to test the safety and immune
response of Dryvax vaccine, by comparing full strength to a 1:5 dilution
in children 2 to 5 years of age. But Dr. William B. Carey, Clinical
Professor of Pediatrics at the Children's Hospital of Philadelphia,
who spent 31 years in primary pediatrics care between 1957 and 1989,
disagrees. Dr. Carey personally gave almost all the immunizations his
patients received, including thousands of smallpox vaccinations up until
about 1970. Dr. Carey raises two important points that seem to have
been overlooked by those who considered the proposed trial on 2 to 5
year old children. He points out that it may not be necessary to dilute
the vaccine at all because there is enough vaccinia virus in each individual
vaccine tube to provide several doses. Dr. Carey points out, that unlike
immunizations preparations for tetanus or measles, of which one must
inject all the liquid that is provided to each person, the smallpox
vaccine vials always contained far more vaccine than one could use for
a single administration. He remembers that doctors had to discard the
excess On some occasions, as when a whole family had to prepare for
an overseas trip, it was possible to divide one vial for all members
with good takes for all. This knowledge seems to have been overlooked
in the present debate. But in light of the experience, he says, "we
must ask whether it is at all necessary to be considering the use of
dilution to solve the supply problem. Besides, any necessary testing
could be done on unimmunized adults 20-30 years of age, who can be fully
consenting."[16]
One of the panel experts
who reviewed the proposal pointed out, the proposed study will not shed
any new light on the 'safety' of Dryvax because it lacks a sufficient
number of subjects. He notes that even if the severe reactions in this
study were to occur at 10-20 fold higher rate, "the small number
of subjects (40) would not allow for detection of this increased rate."
[Steven Ebert, Pharm.D] Furthermore, he notes, studies had already shown
that "immunization to young children usually resulted in vaccine
'take' similar to that in young adults." Since a recent study showed
Dryvax to be immunogenic, one can, by inference, expect that it would
still be effective in young children. Therefore, this one panel member
concludes: "this study is unnecessary."
An examination of the protocol
and reports by the panel of experts, underscores the pitfalls of the
current research protection system: those who evaluate clinical trials
through the lenses of the federal regulations (45 CFR 46.404-408; 21
CFR 50.51-54) tend to ignore the overarching moral issues. By focusing
entirely on the imperfectly formulated regulatory sections in isolation,
they tend to approve experiments in which the welfare of some children
will be compromised-as if they were "canaries in the mines"-contradicting
the Maryland Court of Appeals landmark decision, which affirmed the
right of children to be protected from research that is not in their
best interest.[17] All too often
research gatekeepers accommodate research proposals that expose children
to pain and risk of harm, by accepting a claimed "benefit from
study participation" where none can be demonstrated. This tendency
reveals a systemic flaw and a deep schism between those who approve
research and those who are recruited for research. Vulnerable, less
fortunate children are unprotected from experiments involving hazards
to which experts acknowledge they would not subject their own children.
The significant risks posed
by exposure to the vaccinia virus vaccine do not fall into any of the
permissible categories of research under Federal Regulations (45 DCF
46.404-406). Yet, two institutional review boards (IRBs) approved the
study, apparently rationalizing the risks by speculating a benefit of
study participation - even when none can be shown. One expert who reviewed
the experiment, Dr. Robert S. Baltimore, (Yale University) claims: "In
this study the participants [2 to 5 year old children] are self selected
for great interest in becoming immune to smallpox," adding, "they
will have received considerable information about the risks." Dr.
Baltimore further argues: "Unless these studies are done the children
who are vaccinated in an emergent situation· will not be able to give
informed consent." But, as Dr. Baltimore must surely know, children
are NOT "self-selected" volunteers, and they are precluded
from giving legally valid informed consent to research until they reach
the age of majority, 18. Dr. Baltimore brushes aside the hazards associated
with the smallpox vaccine, stating: "The minor discomforts of the
vaccine are seen in many vaccines but do not represent a major concern."
[18]
Dr. Baltimore's statement
should give rise to deep concern among ethical and responsible professionals
and government officials about whose children are being conscripted
and the context and conditions of their recruitment. His statement and
expectations from 2 to 5 year old children is bereft of the understanding
that most parents - even those with minimal education--have about the
capabilities of such young children. The UCLA Human Subjects Submission
Form states how recruitment will occur: "parents will be approached
during the child's well care visit... Secondarily, we may enroll children
from the surrounding community with notification of the child's primary
care provider." What compelling (but misleading) argument and/or
inducements will cause parents to suspend their intuitive parental caution
and enroll their 2 to 5 children in a vaccine trial that is fraught
with hazards and discomfort in an unnecessary vaccine dilution experiment?
Consent Form Misleads and
Misinforms Parents:
The "informed consent"
form presented to parents misrepresents the fact that the children sought
-in Cincinnati and Los Angeles - are not at any particular risk of exposure
to smallpox, and would, therefore, be unlikely to benefit from the vaccine
if no attack occurs. Furthermore, the consent form fails to provide
parents with forthright, illustrated information about the nature of
the known severe adverse reactions to the vaccine.[19]
Parents are told about $120 in reimbursement and a $40 gift certificate
for those children who complete the study-even before they are (nonchalantly)
"informed" about risks. Indeed, the report by Dr. Neal Halsey,
a member of the expert review panel, notes, "The consent document
should provide more complete information and avoid language that minimizes
the potential risks from this vaccine. Specifically, there is no mention
that 1/3 of adults who received Dryvax had sufficient discomfort and
/or inability to use their arm that they missed school or work."
Furthermore, the consent form misinforms and misleads parents with repeated
false assurances: "As with all vaccines or drugs, there is the
possibility that your child could develop an allergic reaction."
The consent documents fail
to inform parents about plans underway requiring states to submit plans
for providing rapid response clinics to vaccinate the public, should
a smallpox infection occur in the United States. Therefore, it is untrue
to claim that pre-emptive vaccination offers any benefit for these children.
If the Informed consent
document is inaccurate, the research is unapprovable.
As has been noted, the consent
documents for the smallpox vaccine trial mislead parents about the extent
of risk and likelihood of severe adverse side effects. This is another
example of the inadequacy of the research review process by local institutional
review boards (IRBs) to protect the interests of children. IRBs had
approved the faulty consent documents. This case demonstrates the special
need for additional oversight to protect children from harmful experiments.
The Alliance for Human Research Protection has called for the establishment
of independent, Children Protection Committees (in addition to review
by IRBs) to serve as the child subjects' advocates, monitoring their
selection, assessing the reasonableness of their parents' consent, and
ensuring that the informed consent signed by parents is in fact informative.
If a bioterrorist attack
occurred, would the smallpox vaccine protect these children?
The rationale given to parents
who would be solicited to volunteer their children for Dryvax vaccine
demonstrates how they can be misled to believe their children are at
risk of exposure to smallpox, and the vaccine trial will protect them.
But there is no evidence of a known risk of exposure to smallpox for
these children. Therefore, the potential benefits of vaccination do
not outweigh the risk of vaccine complications. Universal vulnerability
to the rapid spread of smallpox - if released anywhere - may continue
to deter its use. Knowledgeable experts, such as Meryl Nass, MD, have
pointed out that although the vaccine is effective against the outbreak
of smallpox as a natural disease, the situation in biological warfare
may be very different, and the precautions used against the former may
be of little use against the latter. The terrorists' goal is to maximize
virulence: they may enhance infectivity by selecting (or creating) pathogens
to which genes for antibiotic resistance and vaccine resistance may
have been added. This means that protective measures that are effective
in routine disease situations may fail when confronted with a bioterrorist
attack. Terrorists may pick any number of pathogens for which there
is no vaccine - such as, tularemia, plague, ebola, or an encephalitis
virus - rather than a pathogen for which the targeted population has
been vaccinated, or maintains a vaccination capability.
Vera Hassner Sharav
President
Alliance for Human Research
Protection
Tel. 212-595-8974
[1]
Centers for Disease Control. June 22, 2001. Vaccinia (Smallpox) Vaccine
Recommendations of the Advisory Committee on Immunization Practices
(ACIP) 2001. Morbidity & Mortality Weekly Report
[2]
Lane JM, et al. Complications of smallpox vaccination, 1968: results
of ten statewide surveys. J. Infectious Disease, 1970; 122: 303-9.
[3]
Lane JM. Editorial. Smallpox vaccination served great purpose, but was
not always benign, Infectious Disease News, March 2002 http://www.infectiousdiseasenews.com/200203/frameset.asp?article=guested.asp
[4]
Frey SE. et al Clinical responses to diluted and undiluted smallpox
vaccine. New England Journal of Medicine, April 25, 2002, 346: 1265-1274.
[5]
Henderson DA, Inglesby TV et al. June 9,1999. Smallpox as a biological
weapon (Consensus Statements of the Working Group on Civilian Biodefense).
Journal of the American Medical Association. 281:2127-37.
[6]Manning
A. Smallpox vaccine carries a dose of risk. Daily Times of Pakistan.
Nov 28, 2002. http://www.dailytimes.com.pk/default.asp?page=story_28-11-2002_pg4_13
[7]
Chase M and Hill G, Ugly Side Effects of Smallpox Vaccine Color Terror
Plans, Wall Street Journal,
Oct 21, 2002, front page.
[8]
World Health Organization. 2001. Smallpox. Weekly Epidemiological Record
76.
[9]
Garrett L. 2000. Betrayal of Trust. New York: Hyperion.
[10]
Marshall E. Bioterror Defense Initiative Injects Shot of Cash. vol 283
pp 1234-5).
[11]
Henderson DA, Inglesby TV et al. June 9,1999. Smallpox as a biological
weapon (Consensus Statements of the Working Group on Civilian Biodefense).
J of the American Medical Association.
[12]
Gillis, J, Okie S. U.S. mounts smallpox vaccine push. The Washington
Post. October 28, 2001.
[13]
Altman L, At the Health Department, the Messengers Still Stumble The
New York Times, October 8, 2002: http://www.nytimes.com/2002/10/08/health/policy/08DOCS.html?pagewanted=print&position=top;
Elias M, Smallpox vaccinations:
A shot in the dark USA TODAY, October 7, 2002
http://www.usatoday.com/news/health/2002-10-07-smallpox-vaccines_x.htm
[14]
FDA website: http://www.fda.gov/ohrms/dockets/dockets/02n0466/02n0466.htm
[15]
Principle 2, Nuremberg Code. http://ohsr.od.nih.gov/nuremberg.php3
[16]
Carey WB. Personal correspondence.
[17]
Maryland Court of Appeals. Higgins vs. Kennedy Krieger Institute, Aug.
16, 2001.
http://www.courts.state.md.us/opinions/coa/2001/128a00.pdf
[18]
Baltimore R Opinion. http://ohrp.osophs.dhhs.gov/dpanel/baltimore.pdf
[19]
CDC slides at: http://phil.cdc.gov/Phil/results.asp?page1
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