Jan 11, 2002 (CIDRAP News) Federal health officials revealed this week that they are working on a plan to use immune globulin derived from the blood of anthrax-vaccinated military personnel for emergency treatment of patients with severe cases of inhalational anthrax, if needed.
The hope is that the experimental treatment would neutralize the toxin produced by Bacillus anthracis, according to Centers for Disease Control and Prevention (CDC) officials. Experience in the recent mailborne anthrax attacks indicates that inhalational anthrax can be treated effectively with antibiotics if recognized early, but antibiotics are ineffective in late stages of the disease because they don't block the anthrax toxin.
CDC officials discussed the plan at a Jan 7 meeting in Washington, DC, with an Institute of Medicine committee that is monitoring the CDC's research on the safety and efficacy of the anthrax vaccine. Information from that meeting was reported in the general news media.
Kathy Harben, a CDC press spokesperson in Atlanta, said the CDC intends to file an investigational new drug (IND) application with the Food and Drug Administration for permission to use immune globulin in anthrax patients. An institutional review board convened by the CDC is currently examining the proposed treatment protocol, she told CIDRAP News.
"Only people with laboratory-confirmed anthrax disease who are severely ill despite antimicrobial therapy will be eligible for the emergency treatment under this IND," Harben said.
Immune globulins are glycoproteins that function as antibodies. Immune globulins derived from the blood of people who have been vaccinated against certain diseases, such as rabies and tetanus, are used for prophylaxis and treatment of those diseases in others. Harben said immune globulins are also used for prophylaxis against infections such as hepatitis B, cytomegalovirus, and respiratory syncytial virus.
More than 500,000 military service members have been vaccinated against anthrax since 1998. Harben said 72 units of blood collected from vaccinated military personnel will be used to prepare a "pilot" batch of immune globulin for the protocol. The blood originally was collected to serve as an anthrax vaccine reference standard. She said she didn't know whether the immune globulin has been prepared yet.
Immune globulin has not been used previously as a treatment for anthrax in humans, according to Harben. She said the experimental protocol is based on "controlled studies in animals and on the overall safety record of other IV [intravenous] immune globulin products licensed for clinical use."
A CDC document explaining the proposed protocol describes the drug as "a sterile solution of neutralizing antibody to B anthracis," Harben reported. She quoted Bradley Perkins, MD, a CDC anthrax expert, as saying that the substance would neutralize the anthrax toxin.
Harben said she didn't know how soon the CDC might have the treatment ready for use, but added, "I'm sure they'd like to do it as quickly as possible."