Elusys Therapeutics Announces Publication Of Data Establishing The Adult Human Dose For Its Inhalational Anthrax Antitoxin, ANTHIM® (obiltoxaximab) Injection

PINE BROOK, N.J., Dec. 20, 2016 /PRNewswire/ -- Elusys Therapeutics, Inc. (Elusys) today announced that the company published data and analyses used to determine the intravenous adult human dose for ANTHIM® (obiltoxaximab) Injection, its treatment for inhalational anthrax.  The animal to human dose translation results are published online at Clinical and Translational Science. ANTHIM received U.S. Food and Drug Administration (FDA) marketing approval in March 2016.  ANTHIM is indicated in adult and pediatric patients for the treatment of inhalational anthrax due to Bacillus anthracis in combination with appropriate antibacterial drugs and for prophylaxis of inhalational anthrax when alternative therapies are not available or are not appropriate.

ANTHIM should only be used for prophylaxis when its benefit for prevention of inhalational anthrax outweighs the risk of hypersensitivity and anaphylaxis. The effectiveness of ANTHIM is based solely on efficacy studies in animal models of inhalational anthrax. There have been no studies of the safety or pharmacokinetics (PK) of ANTHIM in the pediatric population. Dosing in pediatric patients was derived using a population PK approach. ANTHIM does not have direct antibacterial activity. ANTHIM should be used in combination with appropriate antibacterial drugs. ANTHIM is not expected to cross the blood-brain barrier and does not prevent or treat meningitis. ANTHIM was developed under the FDA's Animal Rule which requires human healthy volunteer safety and PK studies in addition to animal efficacy studies. The Animal Rule applies to approval of drugs and biologics intended to treat serious or life-threatening conditions caused by exposure to lethal or permanently disabling substances and for which clinical efficacy studies in humans are unethical or unfeasible.

The article, Animal-to-Human Dose Translation of Obiltoxaximab for Treatment of Inhalational Anthrax Under the U.S. FDA Animal Rule, describes Elusys' approach for the selection and justification of the clinical dose of obiltoxaximab for treatment of inhalational anthrax in humans. Human dosing is based on translation of efficacy, PK and pharmacodynamic (PD) data from healthy and infected animal studies to humans using observed data and simulations based on validated population PK and survival models.

The human dose was selected and justified by comparing observed obiltoxaximab exposures in healthy and infected animals to observed exposures in healthy humans, to simulated exposures in healthy and infected humans, and to serum protective antigen (PA) levels in infected animals.  In humans, at a 16 mg/kg intravenous dose, obiltoxaximab area under the concentration-time curve (AUC) was >2 times that in animals, while maximum serum concentrations were comparable to those in animals and were maintained in excess of the concentration required for PA neutralization in infected animals for 2-3 weeks. 

"Translation of animal to human dosing is a key tenet of the FDA Animal Rule and we are proud that ANTHIM is one of the very few products that have been approved under the Animal Rule," said Elizabeth Posillico, PhD, President and Chief Executive Officer of Elusys. "Elusys is pleased to publish the data and analyses supporting selection of the final therapeutic dose of ANTHIM for the treatment of inhalational anthrax."

The full manuscript of the article is currently accessible on the Clinical and Translational Science website and published in the December 2016 issue of the journal.

In November 2015, Elusys was awarded a $45M delivery order from the U.S. government to produce ANTHIM for the U.S. Strategic National Stockpile, the U.S. government's repository of critical medical supplies for public health emergency preparedness.

ANTHIM is a monoclonal antibody that binds to the protective antigen (PA) component of anthrax toxin. ANTHIM's toxin neutralizing activity prevents entry of anthrax toxin into susceptible cells, avoiding further spread of the toxin throughout the body and the ensuing tissue damage that leads to death. ANTHIM is supplied as single-dose vials for IV infusion.

Anthrax is a life-threatening infectious disease caused by B. anthracis.  Cases of inhalational anthrax in humans can occur through intentional spread of B. anthracis spores as a biowarfare or bioterrorism agent. B. anthracis spores introduced through the lungs lead to inhalational anthrax, which is deadly in humans. 

IMPORTANT SAFETY INFORMATION, Including BOXED WARNING

WARNING: HYPERSENSITIVITY and ANAPHYLAXIS
Hypersensitivity reactions, including anaphylaxis, have been reported during ANTHIM infusion. ANTHIM should be administered in monitored settings by personnel trained and equipped to manage anaphylaxis. Stop ANTHIM infusion immediately and treat appropriately if hypersensitivity or anaphylaxis occurs.

WARNINGS AND PRECAUTIONS
Hypersensitivity and anaphylaxis have been reported during the IV infusion of ANTHIM. Due to the risk of hypersensitivity and anaphylaxis, ANTHIM should be administered in monitored settings by personnel trained and equipped to manage anaphylaxis. Monitor individuals who receive ANTHIM closely for signs and symptoms of hypersensitivity reactions throughout the infusion and for a period of time after administration. Stop ANTHIM infusion immediately and treat appropriately if hypersensitivity or anaphylaxis occurs. Pre-medication with diphenhydramine is recommended prior to administration of ANTHIM. Diphenhydramine pre-medication does not prevent anaphylaxis, and may mask or delay onset of symptoms of hypersensitivity.

ADVERSE REACTIONS
The safety of ANTHIM has been studied only in healthy volunteers. It has not been studied in patients with inhalational anthrax. The most frequently reported adverse reactions were headache, pruritus, infections of the upper respiratory tract, cough, vessel puncture site bruise, infusion site swelling, urticaria, nasal congestion, infusion site pain, and pain in extremity.

USE IN SPECIFIC POPULATIONS
Pediatric Use: There have been no studies of the safety or PK of ANTHIM in the pediatric population.

To see the complete prescribing information for ANTHIM, click here.

The ANTHIM program was supported primarily with federal funds from the Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority (BARDA), the Department of Health and Human Services (HHS) under Contract numbers HHSO100201000026C, fully funded at $140.9 million, and HHS0100201100034C, currently funded at $57.0 million.

About Elusys Therapeutics, Inc.
Elusys Therapeutics, a private company based in Pine Brook, NJ, is focused on the development of antibody therapeutics for the treatment of infectious disease. In March 2016, the U.S. Food and Drug Administration (FDA) approved ANTHIM (obiltoxaximab) Injection (www.anthim.com), the company's monoclonal antibody (mAb) anthrax antitoxin, for the treatment of inhalational anthrax due to Bacillus anthracis in combination with appropriate antibacterial drugs, and for prophylaxis of inhalational anthrax when alternative therapies are not available or are not appropriate. Elusys has received over $240 million in development grants and contracts from the U.S. Department of Defense (DoD), National Institutes of Health (NIH) and BARDA. Current investors include Essex Woodlands Health Ventures LLC, Invesco Private Capital, Crescendo Ventures, MedImmune Ventures and Pfizer. For more information, visit www.elusys.com. 

SAFE HARBOR STATEMENT
This announcement includes statements that are forward-looking within the meaning of the Private Securities Litigation Reform Act of 1995. This release includes forward-looking statements. Any statements, other than statements of historical fact, including statements regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects, plans and objectives of management, and any other statements containing the words "believes", "expects", "anticipates", "plans", "estimates" and similar expressions, are forward-looking statements. Such statements are based upon the current beliefs and expectations of management that are subject to risks, uncertainties and other important factors that could cause the company's actual results to differ materially from those indicated by such forward-looking statements. The guidance in this presentation is only effective as of the date given and will not be updated or affirmed unless and until the Company publicly announces updated or affirmed guidance.

SOURCE Elusys Therapeutics, Inc.

Related Links

http://www.elusys.com