- An estimated 500,000 first responders, lab and hospital
workers will receive smallpox vaccine, the Department of Health and Human
Services (DHHS) announced yesterday.
-
- This is an interesting announcement, because to my knowledge
there exist no FDA-licensed smallpox vaccines.
-
- There are three vaccine candidates whose safety and efficacy
are uncertain at this time.
-
- The first vaccine made available was named Dryvax, which
was pulled out of storage after approximately thirty years. Initial reports
indicated that a 1:5 dilution yielded 70% efficacy. However, recent reports
indicated that this diluted old vaccine was nearly 100% effective.
-
- Which is it?
-
- Furthermore, a 1999 report in Science noted that the
rubber seals on the vials were deteriorating, and that 1/4 of the vials
"were suspect." Are the suspect vials being diluted to make new
vaccine also?
-
- The second vaccine comes from the Aventis stockpile,
allegedly "lost" for decades. Millions of doses of vaccine do
not get lost. Vaccine lots are required to have a documented testing history,
and both the manufacturer and FDA should have records on file of the dates
the lots were released and their specifications at the time.
-
- For both these ancient vaccine stockpiles, there exists
no approved method by which FDA can legally "relicense" them
for current use based on test results generated today. There is no way
long-expired product can be "regenerated" for licensure within
current FDA regulations.
-
- The third vaccine candidate is the Acambis (previously
Oravax, using Baxter as subcontractor) smallpox vaccine. This is a new
vaccine whose makeup, as well as its safety and efficacy profile, have
not been publicly discussed. The FDA finalized a rule May 30, 2002 for
accepting animal tests in lieu of human tests for efficacy of bioterrorism
drugs and vaccines. This opens the door for the new vaccine to receive
a full FDA license.
-
- An article in this month's Emerging Infectious Diseases
(CDC) by James LeDuc and Peter Jahrling et al indicates that the Acambis
vaccine is in Phase I trials and licensure is not expected until sometime
in 2003.
-
- When will the public and medical professionals learn
all the details needed to make an informed decision about using this new
product? This information is not releasable by FDA until after licensure.
One hopes that the vaccine will not be used until adequate safety testing
has taken place: Phase I trials do not provide thorough information on
drug and vaccine safety.
-
- It thus appears that three unlicensed vaccines may soon
be available for use in 500,000 Americans. Potentially severe consequences
are anticipated in those with eczema, HIV infection, other forms of immune
deficiency, and cancers (who are receiving radiation or chemotherapy).
There may be other, unknown risk factors that predispose to serious vaccine
complications.
-
- The anticipated extent of spread of the varicella virus
to contacts of the 500,000 has not been publicly discussed, nor have measures
to minimize such spread, although taking such steps is a very important
part of protecting the health of contacts. Recall that most of the 500,000
are involved in direct patient care: their contacts are the very people
most at risk of varicella's spread.
-
- Are the 500,000 expected to acquiesce to receiving an
experimental vaccine(s)? Will they be asked to sign an informed consent,
and will the consent ask them to give up any rights to compensation for
injuries sustained as a result of vaccination? Will they be placed into
clinical trials comparing the three vaccine candidates? Who will pay for
deaths and injuries to these vaccine recipients that occur as a result
of vaccination? Who will pay for deaths and injuries in their contacts?
-
- Does it make good sense to perform this experiment with
all our nation's first responders and a sizable chunk of our lab techs
and physicians? Or does it make more sense to start vaccinations slowly
and observe closely for problems, so they can be mitigated prior to vaccinating
large numbers of critical personnel?
-
- I am a primary care physician with a hospital practice,
and I may be one of the designated half million. I daresay that if offered
the vaccine, I will not be a "taker". How many of the 500,000
intend to comply with this DHHS directive?
|
