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Ervebo Ebola Vaccine

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October 26, 2021
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Ervebo (rVSV-ZEBOV) Ebola Vaccine Description

Ervebo, Ebola Zaire Vaccine, Live, formerly known as V920 (rVSV-ZEBOV-GP), is a recombinant, replication-competent Ebola vaccine. Merck's Ervebo vaccine's active ingredient is live Vesicular Stomatitis Virus (VSV), in which its surface protein has been replaced with that of Zaire ebola virus disease (EVD). In addition, it was genetically engineered to express the main glycoprotein from the Zaire ebolavirus to provoke a neutralizing immune response to the Ebola virus.

Inactive ingredients include recombinant human serum albumin, tromethamine (Tris) buffer. In addition, this vaccine contains a trace amount of rice protein.

People cannot get the Ebola virus disease (EVD) from the Ervebo vaccine. ERVEBO does not protect against other species of Ebolavirus or Marburgvirus.

Ervebo is the first Ebola vaccine currently licensed by the U.S. Food and Drug Administration (FDA) to prevent EVD. And this Merck vaccine was authorized for use in the European Union by the European Medicines Agency on November 11, 2021 - (EMEA/H/C/004554).

The Ervebo Ebola Zaire vaccine (live, attenuated), v920; rVSV-ZEBOV; Drugbank's Accession Number: DB15595. ATC code: J07BX02. STN: 125690. Clinical Reviewer: Rebecca Reindel.

Ervebo (rVSV-ZEBOV) Ebola Vaccine History

On January 8, 2021, the U.S. CDC's Advisory Committee on Immunization Practices (ACIP) recommends the use of the rVSVΔG-ZEBOV-GP Ebola vaccine (Ervebo) in the U.S. for preexposure vaccination for adults aged ≥18 years who are at the highest risk for potential occupational exposure to Ebola virus species Zaire ebolavirus because they are responding to an outbreak of EVD, work as health care personnel at federally designated Ebola treatment centers in the USA, or work as laboratorians or other staff at biosafety level 4 facilities in the USA.

The U.S. FDA granted a Priority Review and a Tropical Disease Priority Review Voucher on September 17, 2019. The FDA also granted Breakthrough Therapy designation for Ervebo to facilitate the vaccine's development and scientific evaluation. And on December 19, 2019, the FDA announced the approval of Ervebo, the first FDA-approved vaccine for preventing EVD caused by Zaire ebolavirus in individuals 18 years of age and older.

On January 12, 2021, leading international health and humanitarian organizations announced establishing a global Ebola vaccine stockpile to ensure outbreak response. With the support of humanitarian organizations, the supply will allow countries to contain future Ebola epidemics by providing timely access to vaccines for populations at risk during outbreaks. In addition, the injectable single-dose Ebola vaccine Ervebo (rVSV∆G-ZEBOV-GP, live) was included. On February 15, 2020, Merck announced that African countries, including the Democratic Republic of the Congo, Burundi, Ghana, and Zambia, have approved the use of Ervebo.

Since the Ervebo vaccination program in central Africa in 2019, approximately 300,000 persons have been vaccinated with the ERVEBO vaccine. Merck manufactures licensed vaccine doses and expects these doses to become available in roughly the 3rd quarter of 2020. The Joint Project Manager for Chemical, Biological, Radiological, and Nuclear Medical (JPM-CBRN) helped provide a test that allowed Merck to test human and non-human primate samples. Comparing the two samples is part of the FDA's requirements for licensure.

Merck & Co. Inc. licensed the global R&D and manufacturing rights from Newlink Genetics Corp.'s phase I Ebola vaccine in 2014. The Public Health Agency of Canada, which initially developed the vaccine, retained noncommercial rights in the agreement.

Ervebo (rVSV-ZEBOV) Ebola Vaccine Indication

The Ervebo vaccine (rVSV-ZEBOV-GP) is indicated to prevent disease caused by Zaire ebolavirus in individuals 18 years of age and older. However, the duration of protection conferred by Ervebo is unknown. In addition, when administered concurrently with antiviral medication, the vaccine's effectiveness, immune globulin (IG), and/or blood or plasma transfusions are unknown.

Ebola cases are sporadic in the U.S. They have resulted from infections acquired by individuals in other countries who then traveled to the U.S. or health care workers who became ill after treating patients with EVD. For example, in September 2014, a man arrived in Dallas, Texas, infected with Ebola, and was treated at a local hospital. This person passed the virus to the healthcare staff.

Ebola virus can be detected in blood after the onset of symptoms. However, it may take up to 3 days after symptoms start for the virus to reach detectable levels. Therefore, the CDC's new Health Alert recommends that Ebola virus testing be conducted only for people who have an epidemiologic risk factor within 21 days of symptom onset and have an Ebola-compatible clinical syndrome.

Following vaccination with the Ervebo vaccine, individuals may test positive for anti-Ebola glycoprotein (GP) antibody and/or Ebola GP nucleic acid or antigens. However, GP-based testing may have limited diagnostic value during vaccine viremia, in the presence of vaccine-derived Ebola GP, and following antibody response to the vaccine. Therefore, the CDC says that a polymerase chain reaction is one of the most commonly used diagnostic methods because of its ability to detect ebola virus disease. 

As of January 12, 2021, the vaccine was administered to more than 350,000 people in Guinea and the 2018-2020 Ebola outbreaks in the Democratic Republic of the Congo under a protocol for "compassionate use."

The WHO published the revised Ebola Vaccine FAQ on January 11, 2020. And the U.S. CDC published 'Ebola Vaccine: Information for U.S. Healthcare Providers' on November 12, 2020.

Ervebo (rVSV-ZEBOV) Ebola Vaccine Efficacy 

Vaccine efficacy was evaluated in a two-part phase 3, open-label, cluster-randomized, controlled ring vaccination trial in Guinea during the 2014–2016 Ebola outbreak in West Africa, says the CDC. In the initial study, clusters of contacts of confirmed EVD patients and contacts of those contacts were offered immediate vaccination or delayed vaccination (21 days after randomization). The primary outcome of interest was the incidence of laboratory-confirmed EVD with onset ≥10 days after randomization. The ten days were selected to account for the incubation period of EVD and the unknown length of time from vaccination to protective immunity development.

Overall, the CDC states the rate of pregnancy loss among pregnant women who received immediate vaccination was not statistically significantly higher than the rate of pregnancy loss among unvaccinated pregnant women. In addition, no external congenital anomalies were detected among live-born infants in either group (n = 44).

Ervebo (rVSV-ZEBOV) Ebola Vaccine Dosage

The Ervebo vaccine (rVSV-ZEBOV-GP) is administered as a single-dose intramuscular injection. You will get this vaccine as an injection at the top of your arm. However, Merck says, 'do not administer Ervebo to individuals with a history of a severe allergic reaction (e.g., anaphylaxis) to any component of the vaccine, including rice protein.' This is because the safety and effectiveness of Ervebo have not been assessed in immunocompromised individuals.

There are no adequate and well-controlled studies of Ervebo in pregnant women. Human data available from clinical trials with Ervebo are insufficient to establish the presence or absence of vaccine-associated risk during pregnancy. Therefore, the decision to vaccinate a pregnant woman should consider the woman's risk of exposure to Zaire ebolavirus. Furthermore, previous clinical studies of Ervebo with seniors did not include sufficient numbers of subjects 65 years of age and older to determine whether they respond differently from younger subjects.

Ervebo (rVSV-ZEBOV) Ebola Vaccine Side Effects

Injection-site side events include injection-site pain, swelling, and redness. The most common injection-site adverse events were injection-site pain (70%), swelling (17%), and redness(12%). The most common systemic adverse events reported following vaccination with ERVEBO were headache (37%), feverishness (34%), muscle pain (33%), fatigue (19%), joint pain (18%), nausea (8%), arthritis (5%), rash (4%) and abnormal sweating (3%). 

Tell your health care provider promptly about any unusual or severe symptoms that develop after you receive this vaccine. You may also report any side effects to Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., at 1-877-888-4231 or directly to Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1-800-822-7967, or report online to www.vaers.hhs.gov.

International Coordinating Group on Vaccine Provision - Ebola Vaccine Stockpile

The ICG manages the Ebola vaccine's global stockpile, created as an additional tool to help control Ebola outbreaks. Ebola outbreaks are relatively rare and unpredictable. Due to limited vaccine quantities, the current Ervebo vaccine is reserved for outbreak response to protect people at the highest risk of contracting Ebola – including health care and frontline workers in an outbreak under a ring vaccination strategy. An initial 6,890 doses will be made available on a priority basis for outbreak response starting January 12, 2021.

Depending on the rate of vaccine deployment, it could take 2 to 3 years to reach the SAGE-recommended level of 500,000 doses for emergency stockpiles of vaccines. WHO, UNICEF, Gavi, and vaccine manufacturers continuously assess options to increase vaccine supply if global demand increases.

The ICG is working with partners and stakeholders to use the Ervebo outbreak response vaccine in the context of an integrated Ebola outbreak response strategy based around early detection, contact tracing, case management, infection prevention and control measures, safe and dignified burials, and raising awareness among the affected communities.

    Ervebo (rVSV-ZEBOV) Ebola Vaccine News

    October 24, 2021 - The WHO Africa Tweeted the 3rd fatality, sixth case, and has been confirmed in the DRC's latest Ebola outbreak

    October 19, 2021 - The ECDC reported three people died, and all cases are from a DRC community in the Beni health zone. Ten patients are hospitalized, including two confirmed and eight suspected cases, and 386 contacts have been established so far, with 322 followed in the last 24 hours, and 140 people have been vaccinated so far. The index case, diagnosed on 8 October and deceased in a health facility, had three family members who died in September, but they were not investigated for Ebola. The detected Ebola strain is 96% similar to the 10th EVD outbreak in the Democratic Republic of the Congo (2018-2020).

    October 13, 2021 - The WHO confirmed a vaccination program had launched in the DRC related to the new Ebola outbreak. About 1,000 doses of the rVSV-ZEBOV Ebola vaccine and other medical supplies were delivered from the capital Kinshasa to Goma city in North Kivu. In addition, around 200 doses were sent to Beni city near the Butsili health area, where the confirmed case was detected. In addition, vaccinators are using the "ring vaccination" approach, where contacts and contacts of contacts are vaccinated. And the DRC has more than 12,000 vaccine doses in Kinshasa that can be deployed if necessary.

    October 11, 2021 - The CEO of GAVI Tweeted 'about 1,000 doses of the rVSV-ZEBOV vaccine are still available in the country (DRC), so vaccination can start immediately to contain this outbreak. And 248,500 supported doses are available in the global stockpile ready to ship in case of need' @GaviSeth.

    October 10, 2021 - The WHO confirmed the recent case was a 3-year-old male who developed symptoms including physical weakness, loss of appetite, abdominal pain, breathing difficulty, dark stool, and blood in their vomit. And died on October 6th. This case follows a cluster of three deaths (two children and their father) who were the boy's neighbors. These three patients died on 14, 19, and 29 September 2021 after developing symptoms consistent with Ebola; however, none were tested for the virus. No vaccination plan was announced for the 'close-contacts.'

    October 8, 2021 - A case of Ebola has been confirmed in the Democratic Republic of the Congo (DRC). The report from the biomedical lab, the INRB, said the positive result came from a 2-year-old in a densely populated neighborhood of the city of BeniDRC's of the epicenters of the 2018-20 Ebola outbreak. The DRC's health minister declined to confirm the information.

    August 17, 2021 - The WHO Africa confirmed the vaccine deployment from Guinea used 2,000 doses from Merck that are being used under the "ring strategy" where people who have come into contact with a confirmed Ebola patient are given the vaccine as first responders and health workers.

    August 17, 2021 - The EMA published updated Procedural steps are taken and scientific information after the Ervebo authorization.

    August 9, 2021 - The WHO reported, 'Guinea has previous experience managing recurring viral hemorrhagic diseases such as EVD and Lassa fever, but reported first time that Marburg Virus Disease has been reported.'

    July 6, 2021 - New York-based Mount Sinai researchers have uncovered the complex cellular mechanisms of the Ebola virus, which could help explain its severe toll on humans and identify potential pathways to treatment and prevention. In a study published in mBio, the team reported how a protein of the Ebola virus, VP24, interacts with the double-layered membrane of the cell nucleus, leading to significant damage to cells and virus replication and propagation disease.

    June 19, 2021 - ThereportedGuinea'sea's 16 confirmed and seven probable cases reportedGuinea'sea's latest Ebola outbreak, in which 11 patients survived, and 12 lives were lost. The WHO delivered around 24,000 Ebola vaccine doses and supported the vaccination of nearly 11,000 people at high risk, including over 2,800 frontline workers. 

    May 3, 2021 - The WHO announced the end of the 12th Ebola outbreak in the Democratic Republic of the Congo, just three months after the first case was reported in North Kivu. The WHO vaccinate nearly 2,000 people at high risk, including over 500 frontline workers.

    April 9, 2021 - Two new confirmed Ebola cases and three probable cases, including three deaths, have been reported by the WHO in Guinea. All new patients are being reported from the Soulouta sub-prefecture in the region of N¶Zerekore. Ring vaccination around these new Ebola cases started as of April 2, 2021. A total of 129 contacts had been vaccinated.

    April 2, 2021 - The WHO AfrTweeted' ed 'Ring vaccination site was set up in Soulouta village, Guinea, one day after a new Ebola case was reported. About 129 contacts linked to the recent case have been vaccinated.

    April 1, 2021 - During the 2018–2020 Ebola virus disease (EVD) outbreak in North Kivu province in the Democratic Republic of Congo, EVD was diagnosed in a patient who had received the recombinant vesicular stomatitis virus-based vaccine expressing a ZEBOV glycoprotein (rVSV-ZEBOV) (Merck). His treatment included an Ebola virus (EBOV)–specific monoclonal antibody (mAb114), and he recovered within 14 days. However, six months later, he presented with severe EVD-like illness and EBOV viremia, and he died. We initiated epidemiologic and genomic investigations that showed that the patient had had a relapse of acute EVD, leading to a transmission chain resulting in 91 cases across six health zones over four months.

    March 25, 2021 - UNICEF confirmed 4,345 people had been vaccinated, including 1,801 frontline staff since the Ebvaccination'son's official launch in Guinea on February 23, 2021.

    March 16, 2021 -  Cumulatively, 30 EVD cases, 15 deaths (CFR: 50%), and eight recoveries have been reported from DR Congo (12 patients; 6 deaths; 2 rescues) and Guinea (18; 9; 6). In addition, seven healthcare workers are amongst the confirmed cases: DR Congo (2) and Guinea (5).

    February 25, 2021 - 'As Ebola immunization scales up in Guinea's neighboring nations are on high alert, urgently preparing to detect, isolate and manage any cases and quickly stamp out potential cross-border outbreaks.  Nine patients, including five deaths, have been reported in Guinea.

    February 23, 2021 - The Ebola disease vaccindosesMerck'sck'sgan in Guinea after receiving Merck's Ervebo rVSV-ZEBOV vaccine from WHO's headquarters in Geneva. The WHO is also deploying over 8,500 vaccine doses received directly from Merck.

    February 18, 2021 - The VOA reported speaking in a virtual news conference from her headquarters in Brazzaville, Republic of Congo, WHO Africa Director Matshidiso Moeti said officials expect an additional 8,600 doses of vaccine from the United States, for a total of nearly 20,000 shots. She expects them to arrive by Sunday and Ebola vaccinations to begin by Monday.

    February 12, 2021 - Media reports indicate the DRC confirmed a third Ebola case in North Kivu. Provincial health minister Eugene Nzanzu Salita said, "We are in a meeting to gather information. The recent outbreak would be the DRC's 12th.

    February 11, 2021 - The BBC reported Eugene Nzanzu Syalita, a DRC health minister, indicated the country would start inoculating people in Masaya, a heath zone near Butembo. In total, 161 people in that area had been traced to the first Ebola patient.

    February 7, 2021 - The Ministry of Health of the Democratic Republic of the Congo (DRC) announced a recent Ebola case in Butembo, a city in North Kivu Province, where a previous outbreak was declared over in June 2020. The Butembo branch of the National Institute of Biomedical Research confirmed Ebola in samples taken from a patient with Ebola-like symptoms who had sought treatment at a local health center. The woman was the wife of an Ebola survivor. She has since died. Butembo was one of the epicenters of the previous Ebola outbreak (11th) in eastern DRC. It is not unusual for sporadic cases to occur following a significant outbreak, says the WHO.

    January 29, 20province'sce'soutbreak in Équateur Province affected 13 of provinces' 18 health zones, with 130 confirmed cases and 55 deaths. The introduction of an Ebola vaccine in the DRC in 2018 enabled the country to mitigate the last three outbreaks impact. About 372,800 people have been vaccinated against Ebola (including 39,859 in Équateur province).

    January 27, 2021 - The journal Nature published a new study: Ebola virus antibody decay–stimulation in a high proportion of survivors. The most increased antibody reactivity was observed around 200 days after an individual had recovered. The model suggests that EBOV antibody reactivity declines over 0.5–2 years after recovery. In a high proportion of healthy survivors, antibody responses undergo rapid restimulation. Vigilant follow-up of survivors and possible elective de novo antigenic stimulation by vaccine immunization should be considered to prevent EBOV viral recrudescence in recovering individuals and mitigate the potential risk of reseeding an outbreak.

    January 27, 202publis'edu'opean Centre for Disease Prevention anddise'sel'publis'ed 'Treatment and vaccines for Ebola virus disease.'

    January 12, 2021 - United Nations agencies and humanitarian partners announced a global Ebola vaccine stockpile to help control future epidemics by ensuring timely vaccine access for high-risk populations during ouAdvisCommittee'see's 2021 - This CDC report summarizes the AdvisCommittee'see's recommendations on Immunization Practices to use the rVSVΔG-ZEBOV-GP Ebola vaccine (Ervebo) in the USA. The vaccine contains rice-derived recombinant human serum albumin and a live attenuated recombinant vesicular stomatitis virus (VSV). The gene encoding the VSV glycoprotein wZaebolavirus'sus'she gene encoding the Ebola virus species Zaebolavirus'sus's glycoprotein. Persons with a history of a severe allergic reaction to rice protein should not receive Ervebo.

    November 2, 2020 - More than 703 new people received the rVSV-ZEBOV-GP vaccine for a cumulative total of 40,065 people vaccinated in the DRC.

    September 30, 2020 - The U.S. CDC issued an Alert - Level 2, centAfrica'sca'sd Precautions, for prospective visitors to centAfrica'sca's DRC area.

    October 13, 2020 - The Lancet study: Longitudinal antibody and T cell responses in Ebola virus disease survivors and contacts: an observational cohort study.

    June 26, 2020 - The World Health Organization marked the end of the 10th outbreak of Ebola virus disease in the Democratic Republic of the Congo. About 303,000 people were vaccinated with the ERVEBO, a recombinant, replication-competent Ebola vaccine.

    May 26, 2020 - Merck and IAVI announced a collaboration to develop an investigational vaccine targeted against the SARS-CoV-2 coronavirus. This vaccine candidate will use the recombinant vesiMerck'sck'stitis virus (rVSV) technology that is the basis of Merck'sck's Ebola Zaire virus vaccine, ERVEBO, the first rVSV vaccine approved for use in humans.

    May 6, 2020 - The Lancet: A systematic review, pregnancy, and breastfeeding in the context of Ebola.

    February 21, 2020 - National Health Authorities register ERVEBO vaccine in the Democratic Republic of Africa, Burundi, Ghana, and Zambia.

    February 14, 2020 - Merck confirmed that four African countries, including the Democratic Republic of the Congo, have approved the ERVEBO vaccine. ERVEBO has now been registered in the following countries in Africa – DRC, Burundi, Ghana, and Zambia. Approvals in additional countries in Africa are anticipated shortly, said Merck. As previously announced, Merck is working to initiate licensed doses and expects these doses to start becoming available in approximately the third quarter of 2020.

    December 19, 2019The U.S. Food and Drug Administration announced the approval of Ervebo, the first FDA-approved vaccine for preventing Ebola virus disease caused by Zaire ebolavirus in individuals 18 years of age and older. Ervebo was determined to be 100% effective in preventing Ebola cases with symptom onset more significant than ten days after vaccination. In addition, no cases of EVD with symptom onset more critical than ten days after vaccination were observed in "he "immed" a "e" "us "er "roup, compared with 10 cases of EVDEMA'sMA's1-"ay "del "yed" cluster group.

    October 18, 2019 - EMA'sMA's human medicines committee recommended granting a conditional marketing authorization in the EuropeaDRC'sRC'sor Ervebo V920 (rVSVΔG-ZEBOVt'at.' July 10, 2019 - DRC'sRC's Minister of Health decided that 'due to the lack of sufficient scientific evidence on the efficacy and safety of other Ebola vaccine candidates, as well as the risk of confusion among the population, it was decided that no additional 'i' al vameMerck'sck'swill be allowed throughout the coun.'' This meMerck'sck's V920 will be the only Ebola Vaccine available in the DRC.

    May 23, 2019The Ethics Committee of the School of Public Health of the University of Kinshasa approved the compassionate belt vaccination protocol amendment for the rVSV-ZEBOV vaccine to expand its targets to pregnant women after the first trimester and lactating women identified as contacts. It is maintained for minors that children can be vaccinated from 6 years. Between 26 November 2018 and 26 May 2019, 319 pregnant women and 603 lactating women registered as contacts could not be vaccinated.

    July 25, 2016 - Merck announced two regulatory milestones for its investigational vaccine for Ebola Zaire, V920 (rVSV∆G-ZEBOV-GP, live attenuated): the U.S. Food and Drug Administration has granted the vaccine candidate Breakthrough Therapy Designation, and the European Medicines Agency has granted PRIME status.

    December 23, 2015 - Merck announced the application for Emergency Use Assessment and Listing for its investigational Ebola Zaire vaccine, V920 (rVSV∆G-ZEBOV-GP, live attenuated), has been accepted for review by the World Health Organization.

    Ervebo Vaccine Clinical Trials

    Merck Announces FDA Approval for ERVEBO® (Ebola Zaire Vaccine, Live). Clinical trial information is available at Merck Vaccines.