Safety and Immunogenicity of Ervebo® and Zabdeno® Booster Vaccines Against Ebola Virus Following Previous Vaccination with the Zabdeno/Mvabea® or Ervebo® Vaccine Schedules in DRC

Launched by INSTITUTE OF TROPICAL MEDICINE, BELGIUM · Nov 6, 2023

Keywords

ClinConnect Summary

This clinical trial is studying the safety and effectiveness of booster vaccines, Ervebo® and Zabdeno®, for people in the Democratic Republic of Congo (DRC) who have already been vaccinated against Ebola virus. The researchers want to find out if these booster vaccines can help strengthen the immune response in individuals who have received either the Zabdeno/Mvabea® or Ervebo® vaccines in the past. Participants will be randomly assigned to receive one of the booster vaccines and will visit the clinic several times over six months to provide blood samples and monitor their health.

To be eligible for the trial, participants must be between 18 and 50 years old and have received their initial Ebola vaccinations more than four months before joining the study. They should also be able to give informed consent and have a valid identification document. Throughout the trial, safety will be closely monitored by tracking any side effects and checking participants' physical health. It's important to note that individuals with a history of Ebola virus disease or certain medical conditions may not be eligible to participate.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Subjects who received either the Ervebo® vaccine (MSD), or the full Zabdeno, Mvabea® vaccine regimen (J\&J) more than 4 months prior to recruitment
• • Subjects between 18 and 50 years of age at time of randomization
• • Subject must be willing and able to provide informed consent
• • The subject must be in possession of an identification card (or other identification document)
• • Agreement to refrain from blood donation and other vaccinations 30 days after booster vaccination
• • Agreement to share and discuss participant's medical history, medical records and concomitant medications when relevant
• Exclusion Criteria:
• • Participants who previously experienced active Ebola Virus Disease (EVD)
• • Receipt of any vaccine (licensed or experimental) within 30 days prior to recruitment
• • Receipt of an additional booster dose of either Ervebo®, Zabdeno®, or any experimental Ebola vaccine
• • Incorrect or incomplete primary vaccination scheme with the Zabdeno, Mvabea® (J\&J) vaccine
• • Administration of immunoglobulins and/or any blood products within three months prior to recruitment.
• • Fever (\>38°C) within last 24 hours prior to recruitment.
• • Any confirmed or suspected immunosuppressive or immunodeficient state (incl. cancer and HIV); asplenia; recurrent severe infections and use of immunosuppressant medication within the last 6 months, except topical or short-term oral steroids.
• • Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, endocrine disorder and neurological illness (mild/moderate well controlled comorbidities are allowed)
• • History of anaphylaxis, allergic disease or reactions to any component of the study vaccines
• • History of bleeding disorder (e.g. factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venipuncture
• • History of any thrombotic disorder, thrombocytopenia, thrombotic thrombocytopenia syndrome (TTP), or heparin-induced thrombocytopenia and thrombosis (HITT)
• • Any other significant disease, disorder, planned surgery, or finding which may significantly affect the ability of the volunteer to participate in the study or impair interpretation of the study data
• • Suspected or known alcohol or drug dependency
• • Subject is not readily available by telephone, email or physical address
• The non-vaccinated control group will also adhere to all the above in- and exclusion criteria, with exemption of:
• • Agreement to refrain from blood donation and other vaccinations 30 days after study vaccination
• • Subjects who received either the Ervebo® vaccine, or the full Zabdeno, Mvabea® vaccine regimen more than 4 months prior to recruitment
• The latter is rather introduced as an additional exclusion criteria:
• • Subjects who received either the Ervebo® vaccine or the full Zabdeno, Mvabea® vaccine regimen