Inhalational Anthrax Treatment, Anthim, Receives FDA Approval

March 22, 2016
Randi Hernandez

Randi Hernandez was science editor at BioPharm International from September 2014 to May 2017.

The BARDA-supported monoclonal antibody was approved both as a treatment after anthrax exposure and as an anthrax prophylactic.

FDA announced on March 21, 2016, it has approved Anthim (obiltoxaximab), a monoclonal antibody (mAb) intravenous injection meant to treat patients after exposure to anthrax. It was also approved as an emergency injectable to prevent the inhalation of anthrax spores in instances where there is a threat of bioterrorism.

Inhalational anthrax occurs when a person inhales the spores of the bacterium Bacillus anthracis. According to the Centers for Disease Control (CDC), inhalational anthrax is the most deadly form of the disease, and without treatment, only about 10–15% of patients with inhalation anthrax survive. With aggressive treatment, says the CDC, about 55% of patients are able to overcome disease. When administered in combination with antibiotics (e.g., levofloxacin, ciprofloxacin and doxycycline), Anthim produced higher survival outcomes compared with the use of antibiotics alone. Although the mAb itself does not have any antibacterial activity, it works by binding to the protective antigen component of anthrax toxin and neutralizing its activity so that it cannot enter cells.

“Elusys is delighted to receive FDA approval for Anthim and, in addition to FDA, we thank the Biomedical Advanced Research and Development Authority (BARDA), the National Institutes of Health (NIH), and the Department of Defense (DoD), as well as our group of prominent biotech investors, for their ongoing collaboration and support,” said Elizabeth Posillico, PhD, president and CEO of Elusys Therapuetics, the drug maker of Anthim. “This marks a historic milestone for our company, resulting from an unprecedented partnership with several government agencies, to develop a new anthrax antitoxin that will be an important addition to the Strategic National Stockpile (SNS) and help protect the safety of our citizens and emergency personnel in the event of biowarfare attack. We are continuing product development to deliver additional treatment options to the SNS and further protect Americans.”

Although bioterrorism is one of the potential origins of inhalational anthrax, people who work with animals and animal hides are also susceptible to breathing in the spores if the animals are infected. There have also been documented cases of anthrax from the ingestion of raw or undercooked meat from infected animals and cases of cutaneous anthrax after exposure to contaminated animal hides. Lastly, in northern Europe, there have been some cases of anthrax as a result of using contaminated needles between drug users.

Sources: FDA, CDC, Elusys Therapeutics