Monoclonal antibody | |
---|---|
Type | Whole antibody |
Source | Human |
Target | Zaire ebolavirus |
Clinical data | |
Trade names | Ebanga |
Other names | Ansuvimab-zykl, mAb114 |
License data | |
Routes of administration | Intravenous |
Drug class | Monoclonal antibody |
ATC code | |
Legal status | |
Legal status | |
Identifiers | |
CAS Number | |
DrugBank | |
UNII | |
KEGG | |
Chemical and physical data | |
Formula | C6368H9924N1724O1994S44 |
Molar mass | 143950.15 g·mol−1 |
Ansuvimab, sold under the brand name Ebanga, is a monoclonal antibody medication for the treatment of Zaire ebolavirus (Ebolavirus) infection. [1] [2]
The most common symptoms include fever, tachycardia (fast heart rate), diarrhea, vomiting, hypotension (low blood pressure), tachypnea (fast breathing) and chills; however, these are also common symptoms of Ebolavirus infection. [1]
Ansuvimab was approved for medical use in the United States in December 2020. [1] [2] [3] It is on the World Health Organization's List of Essential Medicines. [4]
The drug is composed of a single monoclonal antibody (mAb) and was initially isolated from immortalized B-cells that were obtained from a survivor of the 1995 outbreak of Ebola virus disease in Kikwit, Democratic Republic of Congo. [5] In work supported by the United States National Institutes of Health and the Defense Advanced Projects Agency, the heavy and light chain sequences of ansuvimab mAb was cloned into CHO cell lines and initial production runs were produced by Cook Phamica d.b.a. Catalent under contract of Medimmune. [6] [7]
Ansuvimab is a monoclonal antibody therapy that is infused intravenously into patients with Ebola virus disease. Ansuvimab is a neutralizing antibody, [5] meaning it binds to a protein on the surface of Ebola virus that is required to infect cells. Specifically, ansuvimab neutralizes infection by binding to a region of the Ebola virus envelope glycoprotein that, in the absence of ansuvimab, would interact with virus's cell receptor protein, Niemann-Pick C1 (NPC1). [8] [9] [10] This "competition" by ansuvimab prevents Ebola virus from binding to NPC1 and "neutralizes" the virus's ability to infect the targeted cell. [8]
Antibodies have antigen-binding fragment (Fab) regions and constant fragment (Fc) regions. The Neutralization of virus infection occurs when the Fab regions of antibodies binds to virus antigen(s) in a manner that blocks infection. Antibodies are also able to "kill" virus particles directly and/or kill infected cells using antibody-mediated "effector functions" such as opsonization, complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity and antibody-dependent phagocytosis. These effector functions are contained in the Fc region of antibodies, but is also dependent on binding of the Fab region to antigen. Effector functions also require the use of complement proteins in serum or Fc-receptor on cell membranes. Ansuvimab has been found to be capable of killing cells by antibody-dependent cell-mediated cytotoxicity. [5] Other functional killing tests have not been performed.[ citation needed ]
Ansuvimab is a monoclonal antibody that is being evaluated as a treatment for Ebola virus disease. [11] Its discovery was led by the laboratory of Nancy Sullivan at the United States National Institutes of Health Vaccine Research Center and J. J. Muyembe-Tamfum from the Institut National pour la Recherche Biomedicale (INRB) in the Democratic Republic of Congo, working in collaboration with the Institute for Research in Biomedicine (IRB) (Bellinzona, Switzerland) and the United States Army Medical Research Institute of Infectious Diseases. [5] [12] Ansuvimab was isolated from the blood of a survivor of the 1995 outbreak of Ebola virus disease in Kikwit, Democratic Republic of Congo roughly ten years later. [5]
In 2018, a Phase 1 clinical trial of ansuvimab was conducted by Martin Gaudinski within the Vaccine Research Center Clinical Trials Program that is led by Julie E. Ledgerwood. [7] [6] [13] Ansuvimab is also being evaluated during the 2018 North Kivu Ebola outbreak. [14]
Ansuvimab has also shown success with lowering the mortality rate from ~70% to about 34%. In August 2019, Congolese health authorities, the World Health Organization, and the U.S. National Institutes of Health promoted the use of ansuvimab, alongside atoltivimab/maftivimab/odesivimab, a similar Regeneron-produced monoclonal antibody treatment, over other treatments yielding higher mortality rates, after ending clinical trials during the outbreak. [15] [16]
The U.S. Food and Drug Administration (FDA) approved ansuvimab based primarily on evidence from a clinical trial (Trial 1/ NCT NCT03719586) of 342 participants with Zaire ebolavirus infection. [3] The trial enrolled newborn, pediatric and adult participants (including pregnant women) with Zaire ebolavirus infection. [3] All participants received standard, supportive care for the disease. [3] In addition to the standard care, participants were randomly assigned to receive either a one-time dose of ansuvimab or one of the three other types of experimental treatments (including one as the control group). [3] The participants and the health care providers knew which treatment was being given. [3] The trial was conducted at four sites in the Democratic Republic of Congo during an outbreak that began in August 2018. [3]
A 2016 paper describes the efforts of how ansuvimab was originally developed as part of research efforts led by Dr. Nancy Sullivan at the United States National Institutes of Health Vaccine Research Center and Dr. J. J. Muyembe-Tamfum from the Institut National de Recherche Biomedicale (INRB) in the Democratic Republic of Congo. [5] [12] This collaborative effort also involved researchers from Institute of Biomedical Research and the United States Army Medical Research Institute of Infectious Diseases. [5] [12] A survivor from the 1995 outbreak of Ebola virus disease in Kikwit, Democratic Republic of Congo donated blood to the project that began roughly ten years after they had recovered. [5] Memory B cells isolated from the survivor's blood were immortalized, cultured and screened for their ability to produce monoclonal antibodies that reacted with the glycoprotein of Ebola virus. Ansuvimab was identified from one of these cultures and the antibody heavy and light chain gene sequences were sequenced from the cells. [5] These sequences were then cloned into recombinant DNA plasmids and purified antibody protein for initial studies was produced in cells derived from HEK 293 cells. [5]
In an experiment described in the 2016 paper, rhesus macaques were infected with Ebola virus and treated with a combination of ansuvimab and another antibody isolated from the same subject, mAb100. Three doses of the combination were given once a day starting 1 day after the animals were infected. The control animal died and the treated animals all survived. [5]
In a second experiment described in the 2016 paper, rhesus macaques were infected with Ebola virus and only treated with ansuvimab. Three doses of ansuvimab were given once a day starting 1 day or 5 days after the animals were infected. The control animals died and the treated animals all survived. [5] Unpublished data referred to in a publication of the 2018 Phase I clinical trial results of ansuvimab, reported that a single infusion of ansuvimab provided full protection of rhesus macaques and was the basis of the dosing used for human studies. [7] [6]
Ansuvimab was developed by the Vaccine Research Center with support of the United States National Institutes of Health and the Defense Advanced Projects Agency. The heavy and light chain sequences of ansuvimab mAb were cloned into CHO cell lines to enable large-scale production of antibody product for use in humans. [6] [7]
In early 2018, [11] a Phase 1 clinical trial of ansuvimab's safety, tolerability and pharmacokinetics was conducted by Dr. Martin Gaudinski within the Vaccine Research Center Clinical Trials Program that is led by Dr. Julie E. Ledgerwood. [7] [6] [13] The study was performed in the United States at the NIH Clinical Center and tested single dose infusions of ansuvimab infused over 30 minutes. The study showed that ansuvimab was safe, had minimal side effects and had a half-life of 24 days. [7] [6]
A license for ansuvimab was obtained by Ridgeback Biotherapeutics in 2018, from the National Institutes of Health-National Institute of Allergy and Infectious Diseases. [17] Ansuvimab was given orphan drug status in May 2019 and March 2020. [18] [19] [20]
During the 2018 Équateur province Ebola outbreak, ansuvimab was requested by the Democratic Republic of Congo (DRC) Ministry of Public Health. Ansuvimab was approved for compassionate use by the World Health Organization MEURI ethical protocol and at DRC ethics board. Ansuvimab was sent along with other therapeutic agents to the outbreak sites. [21] [22] [13] However, the outbreak came to a conclusion before any therapeutic agents were given to patients. [13]
Approximately one month following the conclusion of the Équateur province outbreak, a distinct outbreak was noted in Kivu in the DRC (2018–20 Kivu Ebola outbreak). Once again, ansuvimab received approval for compassionate use by WHO MEURI and DRC ethic boards and has been given to many patients under these protocols. [13] In November 2018, the Pamoja Tulinde Maisha (PALM [together save lives]) open-label randomized clinical control trial was begun at multiple treatment units testing ansuvimab, atoltivimab/maftivimab/odesivimab (REGN-EB3) and remdesivir to ZMapp. Despite the difficulty of running a clinical trial in a conflict zone, investigators have enrolled 681 patients towards their goal of 725. An interim analysis by the Data Safety and Monitoring Board (DSMB) of the first 499 patient found that ansuvimab and REGN-EB3 were superior to the comparator ZMapp. Overall mortality of patients in the ZMapp and remdesivir groups were 49% and 53% compared to 34% and 29% for ansuvimab and REGN-EB3. When looking at patients who arrived early after disease symptoms appeared, survival was 89% for ansuvimab and 94% for REGN-EB3. While the study was not powered to determine whether there is any difference between REGN-EB3 and ansuvimab, the survival difference between those two therapies and ZMapp was significant. This led to the DSMB halting the study and PALM investigators dropping the remdesivir and ZMapp arms from the clinical trial. All patients in the outbreak who elect to participate in the trial will now be given either ansuvimab or REGN-EB3. [23] [24] [15] [14]
In October 2020, the U.S. Food and Drug Administration (FDA) approved atoltivimab/maftivimab/odesivimab (Inmazeb, formerly REGN-EB3) with an indication for the treatment of infection caused by Zaire ebolavirus. [25]
In immunology, antiserum is a blood serum containing antibodies that is used to spread passive immunity to many diseases via blood donation (plasmapheresis). For example, convalescent serum, passive antibody transfusion from a previous human survivor, used to be the only known effective treatment for ebola infection with a high success rate of 7 out of 8 patients surviving.
Regeneron Pharmaceuticals, Inc. is an American biotechnology company headquartered in Westchester County, New York. The company was founded in 1988. Originally focused on neurotrophic factors and their regenerative capabilities, giving rise to its name, the company then branched out into the study of both cytokine and tyrosine kinase receptors, which gave rise to their first product, which is a VEGF-trap.
The Vaccine Research Center (VRC), is an intramural division of the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), US Department of Health and Human Services (HHS). The mission of the VRC is to discover and develop both vaccines and antibody-based products that target infectious diseases.
A neutralizing antibody (NAb) is an antibody that defends a cell from a pathogen or infectious particle by neutralizing any effect it has biologically. Neutralization renders the particle no longer infectious or pathogenic. Neutralizing antibodies are part of the humoral response of the adaptive immune system against viruses, intracellular bacteria and microbial toxin. By binding specifically to surface structures (antigen) on an infectious particle, neutralizing antibodies prevent the particle from interacting with its host cells it might infect and destroy.
Ebola, also known as Ebola virus disease (EVD) and Ebola hemorrhagic fever (EHF), is a viral hemorrhagic fever in humans and other primates, caused by ebolaviruses. Symptoms typically start anywhere between two days and three weeks after infection. The first symptoms are usually fever, sore throat, muscle pain, and headaches. These are usually followed by vomiting, diarrhoea, rash and decreased liver and kidney function, at which point some people begin to bleed both internally and externally. It kills between 25% and 90% of those infected – about 50% on average. Death is often due to shock from fluid loss, and typically occurs between six and 16 days after the first symptoms appear. Early treatment of symptoms increases the survival rate considerably compared to late start. An Ebola vaccine was approved by the US FDA in December 2019.
Zaire ebolavirus, more commonly known as Ebola virus, is one of six known species within the genus Ebolavirus. Four of the six known ebolaviruses, including EBOV, cause a severe and often fatal hemorrhagic fever in humans and other mammals, known as Ebola virus disease (EVD). Ebola virus has caused the majority of human deaths from EVD, and was the cause of the 2013–2016 epidemic in western Africa, which resulted in at least 28,646 suspected cases and 11,323 confirmed deaths.
Brincidofovir, sold under the brand name Tembexa, is an antiviral drug used to treat smallpox. Brincidofovir is a prodrug of cidofovir. Conjugated to a lipid, the compound is designed to release cidofovir intracellularly, allowing for higher intracellular and lower plasma concentrations of cidofovir, effectively increasing its activity against dsDNA viruses, as well as oral bioavailability.
ZMapp is an experimental biopharmaceutical drug comprising three chimeric monoclonal antibodies under development as a treatment for Ebola virus disease. Two of the three components were originally developed at the Public Health Agency of Canada's National Microbiology Laboratory (NML), and the third at the U.S. Army Medical Research Institute of Infectious Diseases; the cocktail was optimized by Gary Kobinger, a research scientist at the NML and underwent further development under license by Mapp Biopharmaceutical. ZMapp was first used on humans during the Western African Ebola virus epidemic, having only been previously tested on animals and not yet subjected to a randomized controlled trial. The National Institutes of Health (NIH) ran a clinical trial starting in January 2015 with subjects from Sierra Leone, Guinea, and Liberia aiming to enroll 200 people, but the epidemic waned and the trial closed early, leaving it too statistically underpowered to give a meaningful result about whether ZMapp worked.
TKM-Ebola was an experimental antiviral drug for Ebola disease that was developed by Arbutus Biopharma in Vancouver, Canada. The drug candidate was formerly known as Ebola-SNALP.
Ebola vaccines are vaccines either approved or in development to prevent Ebola. As of 2022, there are only vaccines against the Zaire ebolavirus. The first vaccine to be approved in the United States was rVSV-ZEBOV in December 2019. It had been used extensively in the Kivu Ebola epidemic under a compassionate use protocol. During the early 21st century, several vaccine candidates displayed efficacy to protect nonhuman primates against lethal infection.
There is a cure for the Ebola virus disease that is currently approved for market the US government has inventory in the Strategic National Stockpile. For past and current Ebola epidemics, treatment has been primarily supportive in nature.
The 2018 Équateur province Ebola outbreak occurred in the north-west of the Democratic Republic of the Congo (DRC) from May to July 2018. It was contained entirely within Équateur province, and was the first time that vaccination with the rVSV-ZEBOV Ebola vaccine had been attempted in the early stages of an Ebola outbreak, with a total of 3,481 people vaccinated. It was the ninth recorded Ebola outbreak in the DRC.
Nancy Jean Sullivan is an American cell biologist researching filovirus immunology and vaccine development. She is a senior investigator and chief of the biodefense research section at the Vaccine Research Center. Her team discovered the monoclonal antibody, mAb114.
Atoltivimab/maftivimab/odesivimab, sold under the brand name Inmazeb, is a fixed-dose combination of three monoclonal antibodies for the treatment of Zaire ebolavirus. It contains atoltivimab, maftivimab, and odesivimab-ebgn and was developed by Regeneron Pharmaceuticals.
Atoltivimab is a Zaire ebolavirus glycoprotein-directed human monoclonal antibody that is part of the fixed-dose combination atoltivimab/maftivimab/odesivimab that is used for the treatment of Zaire ebolavirus.
Maftivimab is a Zaire ebolavirus glycoprotein-directed human monoclonal antibody that is part of the fixed-dose combination atoltivimab/maftivimab/odesivimab that is used for the treatment of Zaire ebolavirus.
Odesivimab is a Zaire ebolavirus glycoprotein-directed human monoclonal antibody that is part of the fixed-dose combination atoltivimab/maftivimab/odesivimab that is used for the treatment of Zaire ebolavirus.
Bamlanivimab is a monoclonal antibody developed by AbCellera Biologics and Eli Lilly as a treatment for COVID-19. The medication was granted an emergency use authorization (EUA) by the US Food and Drug Administration (FDA) in November 2020, and the EUA was revoked in April 2021.
Ridgeback Biotherapeutics is a Miami-based biotechnology company, primarily known for its involvement in developing a successful COVID-19 medication.
John R. Mascola is an American physician-scientist, immunologist and infectious disease specialist. He was the director of the Vaccine Research Center (VRC), part of the National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH). He also served as a principal advisor to Anthony Fauci, director of NIAID, on vaccines and biomedical research affairs. Mascola is the current Chief Scientific Officer for ModeX Therapeutics.