New Drugs May Protect Against Smallpox
Drugs Could Provide Alternative to Smallpox Vaccination
March 13, 2003 -- Experimental new drugs may offer protection
from the smallpox virus when given days before or after infection and provide a
valuable alternative to the controversial smallpox vaccine. New animal studies
suggest that the drugs, which still have not been tested in humans, may be
effective against the smallpox virus whether they are given up to five days
prior or three days following exposure to the virus.
The findings were presented this week at the American Society
for Microbiology's Biodefense Research Meeting in Baltimore.
In the study, researcher Earl R. Kern, PhD, of the University
of Alabama at Birmingham, and colleagues tested four versions of a compound
called cidofovir (CDV), which blocks the activity of the variola virus, which
causes smallpox, cowpox, and other related diseases in humans and animals. Two
of the versions proved especially effective in halting the deadly action of the
virus in mice infected with cowpox.
Researchers say it's the first time an oral version of the drug
has been shown to protect against a potentially deadly pox-type virus when
given several days before infection or within one to three days after exposure.
Previous studies showed an oral version to be poorly absorbed.
They say the findings suggest that people who cannot safely be
vaccinated against the smallpox virus due to potential side effects may be
protected by taking the drug several times a month. But more research is needed
to determine if the drug is safe for human use.
The drug was developed as part of a national research effort to
design new drugs that can fight the smallpox virus. Other treatments discussed
at the meeting included using proteins produced by the immune system, known as
interferons, to treat people infected with the virus.
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