Profectus BioSciences Inc., a developer of next generation vaccines for high value targets in biodefense, infectious, and emerging diseases, presented on the development of its rVSV- vectored Ebola and Marburg virus vaccine at the Filovirus Medical Countermeasures (MCM) Workshop held in the National Institutes of Health (NIH) Fishers Lane Conference Center in Rockville, MD.
In a release, the Company noted event details:
The two day meeting was sponsored by the NIH's National Institute of Allergy and Infectious Diseases (NIAID), the Food and Drug Administration (FDA), the Department of Defense Joint Vaccine Acquisition Program (DoD-JVAP), the Assistant Secretary for Preparedness and Response (ASPR), and the Biomedical Advanced Research and Development Authority (BARDA).
The meeting was opened with a series of presentations by members of the Filovirus Animal Non-Clinical Group (FANG), a US interdepartmental and interagency group established to support and facilitate the advanced development of filovirus MCM. These presentations outlined progress in developing the animal model, challenge materials, and assays needed for product testing in support of FDA licensure of safe and effective filovirus MCM. The challenge materials group described the selection of highly virulent, low passage viruses isolated from cases of fatal human disease for use in the non-human primate protection studies that together with human safety will form the basis of licensure. The low passage viruses selected for these challenge studies are Sudan ebolavirus variant Gulu (S-EboV), Zaire ebolavirus variant Kikwit (Z- EboV), and Marburgvirus variant Angola (MarV).
In his presentation at the Workshop, Dr. John H. Eldridge, CSO of Profectus, described the tri-valent rVSV vectored Ebola and Marburg virus vaccine being developed by Profectus. The vaccine is based on the live attenuated rVSVINN4CT1 clinical vector, which has successfully completed phase 1 safety and immunogenicity testing as an HIV vaccine candidate (HVTN trial 090). To provide protection against all filoviruses, the Profectus vaccine contains a blend of three rVSVN4CT1 vectors expressing the G proteins from S-EboV, Z- EboV, and MarV. In support of animal model development, Profectus provided the Z-EboV-rVSVN4CT1 and MarV-rVSVN4CT1 vaccines for two FANG-coordinated non-human primate challenge studies conducted under NIAID's preclinical services program. In the first study, a single IM dose of the Z-EboV-rVSVN4CT1 vaccine completely protected 3 cynomolgus macaques against challenge 28 days later with a lethal dose (1,000 pfu) of low passage Z-EboV, while 3 non-vaccinated macaques succumbed to lethal disease. Twenty eight days after the first challenge, the protected macaques were then challenged with a lethal dose (1,000 pfu) of low passage S-EboV. Two of three were protected, even though S-EboV is distantly related to Z-EboV. In the second study, a single dose of the MarV-rVSVN4CT1 vaccine completely protected 2 cynomolgus macaques against lethal challenge 28 days later with low passage MarV, while 2 non-vaccinated macaques succumbed.
Dr. Eldridge said: "Profectus is indebted to the NIH for providing the grant funding that allowed us to bring the tri-valent N4CT1-vectored filovirus vaccine to late stage preclinical development, and to the FANG for including our vaccine in their challenge studies. To my knowledge, Profectus has the only vaccine platform that to date has demonstrated single dose protection against the highly virulent, low passage viruses that will be the standard for licensure. I also wish to acknowledge the contributions made by Drs. Heinz Feldmann of the NIH Rocky Mountain Laboratories and Thomas Geisbert of the Galveston National Laboratory. Without their help and collaboration we would not have obtained the early protection data needed for our investment in this program."
The Profectus rVSV vaccine delivery vector is a replication competent form of the Indiana serotype of VSV that has been genetically attenuated for safe human use (rVSVINN4CT1). This vector has now been shown to be safe and immunogenic in normal healthy adults and will soon be tested as a therapeutic in HIV infected subjects. Profectus has also identified additional vesiculovirus vectors that are immunologically non-cross reactive with VSV, and that have been attenuated using similar genetic manipulations. This family of vectors has been designed to rapidly induce high level antibody responses specific for the surface glycoproteins of emerging infectious disease and bio-threat agents such as those causing viral hemorrhagic fever (Ebola, Marburg, Lassa), viral encephalitis (VEE, EEE, and WEE), and viral arthralgic disease (Chikungunya).
NIAID conducts and supports research--at the NIH, throughout the United States, and worldwide--to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses.
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