The Food and Drug Administration has approved the first drug for treating smallpox, a response to experts' fears that the virus could be used as a bioweapon.
TPOXX, or tecovirimat, is taken orally to treat smallpox "to mitigate the impact of a potential outbreak," pharmaceutical company SIGA Technologies said in a statement.
The World Health Organization declared smallpox eradicated in 1980, and vaccination for Americans against the virus was stopped, according to the Centers for Disease Control and Prevention.
The approval of the drug addresses concerns the smallpox virus could be used in biological warfare.
"This new treatment affords us an additional option should smallpox ever be used as a bioweapon," FDA Commissioner Scott Gottlieb, M.D, said in a statement.
There exists "no immediate, direct threat of a bioterrorist attack using smallpox," according to the CDC.
Researchers tested the drug's effectiveness against smallpox through studies involving animals infected with the virus. The drug was also tested with human volunteers not infected with smallpox.
Headache, nausea, and abdominal pain remained the commonly reported side effects.
The virus spread largely through direct contact with people, said the FDA. Symptoms usually appeared 10 to 14 days after infection. They included fever, exhaustion, headache and backache, as well as a rash initially consisting of small, pink bumps progressing to pus-filled sores.
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