DARPA researchers find new method to treat previously lethal doses of radiation

By: Mark Rockwell
GSN Magazine

Researchers working for the Defense Advanced Research Projects Agency (DARPA) have found a new way to treat lethal doses of radiation with antibiotics and a natural protein.

The scientists’ search, said DARPA, for new radiation countermeasures for troops that might offer more effective treatment for extreme exposure and timely, storable solutions is a high priority.

The DARPA-funded research effort determined that a cocktail of an antibiotic and a protein fight radiation sickness more effectively when they are combined than when used separately. It said while doctors have used antibiotics to treat radiation sickness, DARPA’s researchers found that adding bactericidal/permeability-increasing protein (BPI), a protein found naturally in immune systems, allowed them to increase the survival rates of mice exposed to toxic levels of radiation to nearly 80 percent. More importantly, said DARPA, the BPI/antibiotic treatment was effective up to a day after exposure to radiation, giving it a significant advantage over other treatments that must be administered within hours of exposure.

“The fact that this treatment can be administered up to a day after radiation exposure is so important,” said Millie Donlon, DARPA’s program manager for the effort. “This is because most of the existing treatments we have require they be administered within hours of exposure to potentially lethal radiation – something that might not always be possible in the confusion that would likely follow such an exposure event.”

The treatment, tested on mice, may be even more effective in humans, said DARPA, because humans are more sensitive to endotoxins treated by BPI.

Both the protein and antibiotic are commonly used drugs already approved by the Food and Drug Administration for use in other scenarios like bone marrow transplants and radiation treatment. They also have a long shelf life, making them easy to stockpile for future use, said the agency.

DARPA said its researchers haven’t yet discovered why the combination of BPI and antibiotics work so well together. What DARPA said they have found was mice that received both of these drugs not only had higher survival rates, but also started generating new bloods cells more quickly. It said this has potential for positive impact on many logistical considerations tied to radiation exposure, such as need for hospital time and requirements for donors and transfusions.

DARPA said the research was part of its Radiation Bio-Dosimetry (RaBiD) program. RaBiD was an effort to develop non- or minimally invasive, portable and low-cost radiation bio-dosimeters, as well as novel radiation mitigation technologies that can be administered 12 or more hours after exposure and provide better than 90-percent survivability to humans. RaBiD began in 2008 and ended in August of last year, it said.