WASHINGTON -- Consider it an anthrax bloodhound, a drug that can swoop into the body, latch onto deadly toxins spewed by anthrax bacteria and get rid of them.
Two years after the anthrax-by-mail attacks, scientists are hard at work on such an antidote.
It's far too soon to be sure it will work. The drug, called ABthrax, did save animals exposed to lethal amounts of anthrax, but human safety tests only recently began.
If the anthrax killer, still at large, struck again, a few hundred doses of the experimental drug are on hand that doctors might be allowed to try. It's one of very few new options in advanced testing despite millions spent on bioterrorism preparedness since 2001.
That's the sobering reality: Medical research takes a lot of time.
If someone showed up sick tomorrow, treatment "probably would not be significantly different," said Dr. Anthony Fauci, infectious disease chief at the National Institutes of Health. "Even though these things are moving pretty rapidly, it still would depend on good antibiotics," and getting quick care to anyone exposed.
Still, steadily increasing scientific knowledge about anthrax and other bioterrorism agents already has brought Americans an added benefit -- better ability to quickly spot and battle naturally occurring new infections like monkeypox and SARS.
"There's a whole different understanding of the importance of everyday, front-line public health," said Michael Osterholm of the University of Minnesota, a bioterrorism expert who advises the federal government.
Two years ago Sunday, a Florida man became the first to die in the attacks, after he apparently inhaled anthrax from a tainted letter sent to his employer, a supermarket tabloid. A string of tainted mailings to members of Congress and the media followed, ultimately killing five people and sickening 17 others. Congress shut down, anthrax leaked from letters infiltrated the postal system, and thousands of people took antibiotics to prevent the bacteria from sickening them.
No one has been charged. However, the FBI says exhaustive scientific testing has revealed certain contaminants and other markers in the mailed anthrax that narrow down how it was made and where it might have originated.
"We have arrived at a point where there are certain things we're looking for," said Michael A. Mason, new chief of the FBI's Washington field office.
"Let me tell you, that investigation has done anything but languish."
Culprit aside, doctors want an antidote in case anthrax reappears. Once anthrax bacteria get into the bloodstream, they produce deadly toxins that antibiotics can't treat.
Usually, the immune system creates antibodies to hunt down and kill a pathogen infecting the body. Anthrax, unfortunately, can kill its victim before those antibodies are produced. So a small biotechnology company, Human Genome Sciences, created a human antibody -- ABthrax -- that can be injected into anthrax victims to hunt down and eliminate the toxin.
A single injection of the highest ABthrax dose saved 90 percent of monkeys who inhaled an otherwise lethal amount of anthrax, findings that NIH's Fauci calls "quite impressive." Now the company has begun safety tests of ABthrax in healthy people.
Here's the rub: Antibodies are very expensive to make. So Human Genome Sciences is seeking federal financial help, reluctant to make much more than the few hundred doses now on hand unless the government commits to buying ABthrax if it proves usable.
ABthrax isn't the only promising option under development, Fauci said. NIH has funded 20 grants to develop other antitoxins, and is working to collect a protective protein from the blood of soldiers vaccinated against anthrax that might work, too.
Despite the slow road to new treatments, more has been learned about this centuries-old disease -- which naturally lives in animals and hibernates in soil -- in the last two years than in preceding decades:
--Its complete genetic makeup was deciphered, showing potential new drug targets.
--Studies are under way of second-generation vaccines that promise to cut in half the number of inoculations needed for protection.
If nothing else, Fauci said all the attention should have raised awareness enough that if anthrax ever reappears, "the emergency room physician will not say, 'Go away and take two aspirin,"' as happened to one anthrax-exposed postal worker who later died.
"That was tragic. I would be astounded if that happened" again.
EDITOR'S NOTE -- Lauran Neergaard covers health and medical issues for The Associated Press in Washington.