Elusys Therapeutics, Inc. Receives FDA Approval For ANTHIM (obiltoxaximab) Injection For The Treatment And Prophylaxis Of Inhalational Anthrax

March 21, 2016 |

16 min read

PINE BROOK, N.J., March 21, 2016 /PRNewswire/ -- Elusys Therapeutics, Inc. (Elusys) today announced that the U.S. Food and Drug Administration (FDA) has approved ANTHIM (obiltoxaximab) Injection, the company’s monoclonal antibody (mAb) anthrax antitoxin. 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.

Infographic: What You Should Know About Anthrax

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.

“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 Chief Executive Officer of Elusys. “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.”

“Maintaining a robust supply of treatment options, including antitoxins and other medical countermeasures, to protect public health and enhance national health security is critical to the safety of our civilians and military personnel. ANTHIM is an important addition to the Strategic National Stockpile and is an example of a successful partnership between government and the biomedical industry to develop critically needed medical countermeasures,” said Clifton R. Lacy, MD, Professor and Director, Institute for Emergency Preparedness and Homeland Security, Rutgers University.

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 intravenous (IV) infusion.

Anthrax is a life-threatening infectious disease caused by Bacillus 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.

Because it is not feasible or ethical to conduct controlled clinical trials in humans with inhalational anthrax, the efficacy of ANTHIM for the treatment of inhalational anthrax is based on efficacy studies in two animal models. The animal efficacy studies are conducted under widely varying conditions, such that the survival rates observed in the animal studies cannot be directly compared between studies and may not reflect the rates observed in clinical practice.

ANTHIM monotherapy administered as a single 16 mg/kg IV dose for the treatment of inhalational anthrax disease resulted in statistically significant improvement in survival relative to placebo in two studies for each species. ANTHIM administered in combination with antibacterial drugs (levofloxacin, ciprofloxacin and doxycycline) for the treatment of systemic inhalational anthrax disease resulted in higher survival outcomes than antibacterial therapy alone in multiple studies where ANTHIM and antibacterial therapy was given at various doses and treatment times. ANTHIM administered as prophylaxis resulted in higher survival outcomes compared to placebo in multiple studies where treatment was given at various doses and treatment times.

IMPORTANT SAFETY INFORMATION

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 intravenous 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. Premedication with diphenhydramine is recommended prior to administration of ANTHIM. Diphenhydramine premedication 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.

About ANTHIM

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 and HHS0100201100034C.

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. 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. 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 (SNS), the U.S. government’s repository of critical medical supplies for public health emergency preparedness. Current investors include Essex Woodlands Health Ventures LLC, Invesco Private Capital, Crescendo Ventures, MedImmune Ventures and Pfizer.. For more information, please 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.

MEDIA BACKGROUNDER

Elusys Therapeutics

Elusys Therapeutics, Inc., a private company based in Pine Brook, NJ, is focused on the development of antibody therapeutics for the treatment of infectious disease.

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 (SNS), the U.S. government’s repository of critical medical supplies for public health emergency preparedness. Elusys has received grants and contracts from the USG totaling over $240 million to support ANTHIM’s development.

In March 2016, ANTHIM (obiltoxaximab) Injection, the company’s monoclonal antibody (mAb) anthrax antitoxin, received approval from the U.S. Food and Drug Administration (FDA) for the treatment of adult and pediatric patients with inhalational anthrax due to Bacillus anthracis in combination with appropriate antibacterial drugs, and for prophylaxis of inhalational anthrax due to B. anthracis when alternative therapies are not available or 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.

About ANTHIM

ANTHIM is a monoclonal antibody (mAb) that binds the protective antigen (PA) component of the anthrax toxin. ANTHIM’s toxin neutralizing activity prevents entry of anthrax toxin into susceptible cells, avoiding the further spread of the toxin throughout the body and the ensuing tissue damage that leads to death.

ANTHIM is produced in a single dose for intravenous (IV) infusion. ANTHIM has been designated an Orphan Drug and was developed under FDA’s “Animal Rule” regulations.

ANTHIM (obiltoxaximab) Data

The efficacy of ANTHIM for treatment and prophylaxis of inhalational anthrax was demonstrated in multiple studies in the cynomolgus macaque and NZW rabbit models of inhalational anthrax. These studies tested the efficacy of ANTHIM compared to placebo and the efficacy of ANTHIM in combination with antibacterial drugs relative to the antibacterial drugs alone. The primary endpoint was survival following challenge with B. anthracis.

Two studies in NZW rabbit and two studies in cynomolgus macaques evaluated treatment with ANTHIM 16mg/kg IV single dose compared to placebo in animals with systemic anthrax. Treatment with ANTHIM alone resulted in statistically significant improvement in survival relative to placebo in both species. Survival rates were 93% and 62% with ANTHIM compared to 0 placebo survivors in rabbits, and 47% and 31-35% survival with ANTHIM compared to 6% or 0% placebo survival in macaques.

ANTHIM administered in combination with antibacterial drugs (levofloxacin, ciprofloxacin and doxycycline) for the treatment of systemic inhalational anthrax disease resulted in higher survival outcomes than antibacterial therapy alone in multiple studies where ANTHIM and antibacterial therapy was given at various doses and treatment times.

ANTHIM administered as prophylaxis resulted in higher survival outcomes compared to placebo in multiple studies where treatment was given at various doses and treatment times. ANTHIM administered as prophylaxis resulted in higher survival outcomes compared to placebo in multiple studies where treatment was given at various doses and treatment times. In one study, cynomolgus macaques were administered ANTHIM 16 mg/kg at 18 hours, 24 hours or 36 hours after exposure. Survival was 6/6 (100%) at 18 hours, 5/6 (83%) at 24 hours, and 3/6 (50%) at 36 hours. Another cynomolgus macaque study evaluated ANTHIM 16 mg/kg administered 72, 48 or 24 hours prior to exposure. Survival was 100% at all three time points (14/14, 14/14, 15/15, respectively) at day 56 (end of study).

IMPORTANT SAFETY INFORMATION

WARNING: HYPERSENSITIVITY and ANAPHYLAXIS

WARNINGS AND PRECAUTIONS

Hypersensitivity and anaphylaxis have been reported during the intravenous infusion of ANTHIM. Due to 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. Premedication with diphenhydramine is recommended prior to administration of ANTHIM. Diphenhydramine premedication does not prevent anaphylaxis, and may mask or delay onset of symptoms of hypersensitivity.

ADVERSE REACTIONS

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.

Key Contracts and Markets

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

The company is pursuing sales of ANTHIM in other countries including military and public health organizations:

Federal agencies responsible for emergency preparedness and public health
Militaries
States/Provinces
Global agencies such as the United Nations and World Health Organization

Ongoing Research and Development

Since 2002, Elusys has received over $240 million in grants and contracts to support ANTHIM’s development, from the Office of the Assistant Secretary for Preparedness and Response (ASPR) of the Biomedical Advanced Research and Development Authority (BARDA), and the National Institute of Allergy and Infectious Disease (NIAID) within the Department of Health and Human Services (HHS). Elusys is continuing product development to deliver additional enhancements to the SNS for field and emergency use.

About Anthrax

Anthrax is a disease caused by Bacillus anthracisⁱ^,ii. While it is primarily a disease of animals, cases of anthrax in humans occur through contact with infected animals or animal products or through intentional spread of B. anthracis spores as a biowarfare or bioterrorism agent.

Anthrax is regarded as a top (“Category A”) biological warfare and bioterrorism threat for a number of reasonsⁱ^{, iii, iv}:

Untreated inhalational anthrax has a high fatality rate.
B. anthracis is widely available. The spores are hardy and tolerant to temperature, humidity, and light.
Techniques for mass production and aerosol dissemination of anthrax have been developed.
B. anthracis has been used in the past as a biological weapon.

To prepare for the possibility of the use of B. anthracis as a biological weapon, the U.S. government acquires and maintains equipment and medical countermeasures for anthrax prevention and treatment as part of the Centers for Disease Control’s (CDC’s) Strategic National Stockpile (SNS)^v. The SNS is a national repository of large quantities of medicines, vaccines, and other medical supplies designed to supplement and expand the capacity of state and local public health departments in the event of a large-scale public health emergency. Medical countermeasures for anthrax maintained in the SNS include antibiotics, antitoxins, and vaccines.

Untreated, the case fatality rate for inhalational anthrax may be as high as 90%^iv. Despite the medical care administered to victims of the 2001 attacks in the U.S., which included multidrug regimens, pleural fluid drainage, and intensive care support, the associated fatality rate was approximately 45%^vi^{, vii}.

Symptoms of inhalational anthrax

Inhalational anthrax develops in two phases; in the first 3-4 days, patients experience flu-like symptoms. A transition to systemic illness follows abruptly, with high fever, shortness of breath, excessive sweating, and shockⁱⁱ.

Meningitis or sepsis can develop.

Because the progression from non-specific to severe, life-threatening symptoms is rapid, the treatment window for inhalational anthrax is brief.

Centers for Disease Control (CDC)

For more information on inhalational anthrax, go to http://www.cdc.gov/anthrax.

ⁱ Turnbull, PC. Anthrax in humans and animals, 4th ed. Geneva, Switzerland: World Health Organization. 2008

ⁱⁱ Inglesby TV, O’Toole T, Henderson DA, et al. Anthrax as a biological weapon, 2002: updated recommendations for management. JAMA 2002;287:223652.

iii CDC Bioterrorism agents. Available at: http://fas.org/biosecurity/resource/documents/CDC_Bioterrorism_Agents.pdf .Accessed January 22, 2016.

^ivUniversity of Pittsburgh Medical Center. Center for Health Security. Anthrax Fact Sheet. Updated 02/26/2015. Available at www.UPMCHealthSecurity.org. Accessed December 15, 2015.

^v DSNS Fact Sheet. 2014. Available at: http://www.cdc.gov/phpr/documents/DSNS_fact_sheet.pdf. Accessed December 14, 2015.

^viHolty JE, Bravata DM, Liu H, Olshen RA, McDonald KM, Owens DK. Systematic review: a century of inhalational anthrax cases from 1900 to 2005. Ann Intern Med. 2006. 144(4):270-80.

^vii Jernigan DB, Raghunathan, PL, Bell, BP, et al. Investigation of bioterrorism-related anthrax, United States, 2002: epidemiologic findings. Emerg Infect Dis. 2002;8:1019-28.