First smallpox treatment one step closer to FDA approval
People haven’t been routinely vaccinated against the disease since the 1970s. Molecular virologist Robin Robinson said, “So it would be catastrophic if it were to reappear accidently or in the case of a bioweapon attack.”
He is the former director of the Biomedical Advanced Research and Development Authority, a federal agency that’s focused on protecting against biological and other threats and that assisted in the drug’s development.
Fears that the disease could be used as a biological weapon have risen in light of anthrax attacks and other terrorist acts of this century.
The National Institute of Allergy and Infectious Diseases classifies smallpox as a Category a priority pathogen, because the disease spreads easily from person to person and can be highly fatal.
Researchers tested how well the drug stops smallpox in animals, while trials to determine the safety and dose of the drug were conducted in people. In monkeys and rabbits infected with viruses related to smallpox, tecovirimat prevented around 90 percent of the animals from dying, said SIGA CEO Phil Gomez. Nearly all of the animals that did not receive the drug died.
A smallpox infection does not produce symptoms right away. After 10 to 14 days, a fever and rash occurs — that’s when a person is most contagious — followed by the formation of poxes.
The drug is meant to be taken at the fever and rash stage. Data from the animal studies, Hruby said, suggest that few poxes will form once the drug is taken and patients will heal more quickly.
Grant Mcfadden, who studies poxviruses at Arizona State University in Tempe and was not involved with the development of tecovirimat, said, “Preparing for disasters comes in different shapes and forms. This is preparing for an infectious disease disaster.”
In the event that smallpox reappears, “you need drugs to actually block the progression of the disease”.
Two million treatments of TPOXX are already in the US Strategic National Stockpile of drugs and supplies for public health emergencies, Gomez said, a move allowed under emergency preparedness legislation. FDA approval of tecovirimat would open the door to studying the drug for other uses (such as a treatment for related poxviruses), assure the supply of the drug and encourage other countries to place the drug in their emergency stocks.
Hruby said, “No one can predict if or when a pox virus is going to pop up and cause problems.” With the drug one step closer to FDA approval, “I’d like to think you can sleep better at night.”