2nd Ebola Zaire Vaccine Candidate Approved for the DRC

Janssen Ad26.ZEBOV/MVA-BN Ebola Zaire vaccine candidate to launch human immunization in Africa
young african boy
Africa (Vax Before Travel)

The ongoing Ebola Zaire virus outbreak in the Democratic Republic of the Congo (DRC) will soon have another preventive vaccine candidate. 

The Strategic Advisory Group of Experts (SAGE) issued new recommendations on May 7, 2019, to address vaccination challenges in the DRC. 

These new SAGE recommendations include: 

  • endorsing operational adjustments that make the vaccination process faster and adjusting the dosage based on available efficacy data
  • expanding the population eligible for vaccination with Merck’s v920 (rVSV-ZEBOV-GP)
  • introducing an additional experimental Ebola vaccine developed by Janssen Divison of Johnson & Johnson
  • redoubling ongoing efforts to train nurses, doctors and medical students from Ebola-affected communities to work on vaccination teams

These SAGE recommendations are good news since 1,045 deaths have been reported since the DRC outbreak began in August 2018. 

Professor Jean-Jacques Muyembe, Director of the INRB and Principle Investigator for the rVSV ZEBOV Ebola vaccine protocol, welcomed these SAGE recommendations. 

“The DRC Presidential Commission on Ebola highly appreciates the new SAGE recommendations for the rVSV- ZEBOV GP vaccine,” said Professor Muyembe, in a press release. 

“I will work with the teams to ensure the recommendations are implemented as soon as possible.”

Despite the use of a highly efficacious vaccine candidate from Merck, the number of new Ebola cases continue to rise, in part due to response teams inability to immediately identify and create vaccination rings around all people at risk of contracting Ebola. 

The SAGE endorsed the use of pop-up and targeted geographic approaches to vaccinate when appropriate. These vaccination approaches have already been used successfully in the field by WHO to make the ring vaccination process faster, more secure, and more responsive to community feedback. 

In addition to vaccinating contacts, and contacts of contacts, SAGE now also recommends vaccinating those who could be part of tertiary chains of transmission, such as people in villages and neighborhoods where cases have been reported within the past 21 days. 

SAGE noted that increasing access to vaccination in the broader community may help enhance community acceptance of the vaccine and other control measures. 

People at the highest risk (contacts and contacts of contacts) will now receive 0.5ml of the V920 vaccine instead of 1ml.

Those for whom a rapid evolution of the immune response is less critical (people who are considered lower-risk / those who could be potentially involved in tertiary transmission) will receive 0.2ml (1/5 of the current dose). 

The SAGE reiterated its previous stance stating the need to assess additional Ebola vaccines. SAGE now additionally recommends the adenovirus 26 vectored glycoprotein / MVA-BN (Ad26.ZEBOV/MVA-BN) investigational Ebola vaccine, developed by the Janssen Divison of Johnson & Johnson. 

The Ad26.ZEBOV/MVA-BN vaccine candidate has been conducting a Phase 3 study to demonstrate the non‐inferiority of a heterologous prime‐boost regimen using Ad26.ZEBOV as prime and MVA‐BN‐Filo as boost administered at different doses at a 56‐day interval.

Compared to the same regimen with the recently released batches of Ad26.ZEBOV and MVA‐BN‐Filo in terms of the humoral immune response against the Ebola virus (EBOV) GP (glycoprotein) as measured by enzyme‐linked immunosorbent assay (ELISA) at 21 days post boost.

The Janssen Ebola virus vaccine candidate is also in a phase 2 study to evaluate the safety, reactogenicity, and immunogenicity of a heterologous 2-dose vaccination regimen using Ad26.ZEBOV and MVA-BN®-Filo in infants aged 4-11 months in Guinea and Sierra Leone

To alert international travelers, the US Centers for Disease Control and Prevention (CDC) expanded its Level 2 Travel Alert regarding the Ebola Zaire outbreak in the DRC.

To schedule a pre-trip travel vaccination counseling session, please visit Vax-Before-Travel.