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CompletedNCT03929757Updated May 25, 2025Results posted

A Study of 2-dose Vaccination Regimen of Ad26.ZEBOV and MVA-BN-Filo in Infants

A Phase 2 interventional study of Ad26.ZEBOV and MVA-BN-Filo in Ebola Virus Disease, sponsored by Janssen Vaccines & Prevention B.V.. Completed at 2 sites in 2 countries. Open to participants aged 4 Months to 11 Months, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-05-25.

Sponsored by Janssen Vaccines & Prevention B.V. (part of Johnson & Johnson) · Phase 2, Interventional, and Prevention

Phase
Phase 2
Study type
Interventional
Enrollment
108
Allocation
Randomized
Ages
4 Months to 11 Months
Sex
All
01

Study summary

The purpose of this study is to assess the safety and reactogenicity of a heterologous 2-dose regimen utilizing Ad26.ZEBOV (first vaccination; Dose 1) and MVA-BN-Filo (second vaccination; Dose 2) administered intramuscularly (IM) on Days 1 and 57, respectively (Main Study) and also to provide the heterologous 2-dose vaccination regimen (Ad26.ZEBOV on Day 1 and MVABN-Filo on Day 57) to participants in the control arm of the main study (Extension Phase).

02

Conditions studied

  • Ebola Virus Disease
03

In context

Hemorrhagic Fever, Ebola

104 studies on the registry are indexed under Hemorrhagic Fever, Ebola; 13 are open to participants now.

This study's enrollment of 108 is above the median of 94 across 81 interventional studies indexed under Hemorrhagic Fever, Ebola.

Browse Hemorrhagic Fever, Ebola studies →

Lead sponsor

Janssen Vaccines & Prevention B.V. is the lead sponsor of 49 studies on the registry; none are open to participants now.

Of its 37 completed or terminated interventional studies of FDA-regulated products, 32 (86%) have results posted.

First submitted after Janssen Vaccines & Prevention B.V. became part of Johnson & Johnson.

Browse Janssen Vaccines & Prevention B.V. studies →All Johnson & Johnson studies →

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
4 Months to 11 Months
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Parent(s) (preferably both if available or as per local requirements)/guardian must sign an form (ICF) indicating that he or she understands the purpose of, and procedures required for the study, and potential risks and benefits of the study, and are willing to allow their child to participate in the study
  • Parent(s)/guardian are willing/able to ensure that their child adheres to the prohibitions and restrictions
  • The parent(s)/guardian must be at or above the age of legal consent in the jurisdiction in which the study is taking place
  • Infant must be healthy in the investigator's clinical judgment (and the parent(s)/guardian) on the basis of medical history, physical examination, vital signs and clinical laboratory tests performed at screening
  • Infant has received all routine immunizations appropriate for his or her age at the time of enrollment as documented in the vaccination cards presented by the parent(s)/guardian. Participants are allowed to catch up on routine immunizations if needed (support for beneficial vaccines may be offered to participants)
  • Extension Phase: Prior enrollment in the control arm of the main study and did not withdraw consent, and receipt of at least the first vaccination (Dose 1) in the main study

Exclusion criteria

Exclusion Criteria:

  • Having received any candidate or other Ebola vaccine
  • History of Ebola virus disease (EVD), or prior exposure to Ebola virus, including travel to an area with a current Ebola outbreak less than 1 month prior to screening
  • Having received any experimental candidate Ad26- or modified vaccinia ankara (MVA)-based vaccine in the past
  • Known allergy or history of anaphylaxis or other serious adverse reactions to vaccines or vaccine products (including any of the constituents of the study vaccines [for example, polysorbate 80, ethylenediaminetetraacetic acid (EDTA) or L-histidine for Ad26.ZEBOV vaccine; tris (hydroxymethyl)-amino methane (THAM) for MVA-BN-Filo vaccine and Neisseria meningitidis polysaccharide or tetanus toxoid for MenACWY]), including known allergy to chicken or egg proteins and aminoglycosides (gentamicin)
  • Presence of acute illness (this does not include minor illnesses such as mild diarrhea or mild upper respiratory tract infection) or axillary temperature greater than or equal to (>=) 37.5 degree celsius on Day 1. Participants with such symptoms will be excluded from enrollment at that time but may be rescheduled for enrollment at a later date
  • Extension Phase: Having received any candidate or other Ebola vaccine
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Phase
Phase 2
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
108 participants (actual)

Study arms

  • Experimental
    Arm 1: Ad26.ZEBOV, MVA-BN-Filo

    Participants will be administered 0.5 mL of Ad26.ZEBOV vaccine (5\*10\^10 viral particles \[vp\]) on Day 1 by intramuscular (IM) injection followed by 0.5 mL of MVA-BN-Filo (1\*10\^8 infectious units \[Inf U\]) vaccine by IM injection on Day 57. Participants will also receive a dose of MenACWY at the 6-months post-dose-2 visit. Upon completion of the main study, participants in the extension phase who were originally randomized to the control arm will receive the same vaccine regimen as the participants in the Ad26.ZEBOV, MVA-BN-Filo arm of the main study.

    Biological: Ad26.ZEBOV · Biological: MVA-BN-Filo · Biological: MenACWY

  • Active comparator
    Arm 2: MenACWY

    Participants will be administered 0.5 mL of MenACWY vaccine by IM injection on Day 1 and Day 57. Participants will also receive a dose of MenACWY at the 6-months post-dose-2 visit.

    Biological: MenACWY

Interventions

  • BiologicalAd26.ZEBOV

    Participants will receive 0.5 mL IM injection of Ad26.ZEBOV as first vaccination.

  • BiologicalMVA-BN-Filo

    Participants will receive 0.5 mL IM injection of MVA-BN-Filo as second vaccination.

  • BiologicalMenACWY

    Participants will receive 0.5 mL IM injection of MenACWY.

06

What researchers measure

Primary outcomes

  1. Main Study: Percentage of Participants With Solicited Local and Systemic Adverse Events (AEs) up to 7 Days Post-dose 1

    An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Solicited local AEs that included injection site pain/tenderness, erythema, induration/swelling, itching at the vaccination site, were pre-defined local (at the injection site) AEs for which participant were specifically questioned and which were noted by participant in their diary for 7 days post vaccination. Solicited systemic events included fever, headache, fatigue/malaise, myalgia, nausea/vomiting, arthralgia and chills.

    Time frame: From dose 1 (Day 1) up to 7 days post-dose 1 (Day 8)

  2. Main Study: Percentage of Participants With Solicited Local and Systemic AEs up to 7 Days Post-dose 2

    An AE is any untoward medical occurrence in a participants participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Solicited local AEs that included injection site pain/tenderness, erythema, induration/swelling, itching at the vaccination site, were pre-defined local (at the injection site) AEs for which participant were specifically questioned and which were noted by participant in their diary for 7 days post vaccination. Solicited systemic events included fever, headache, fatigue/malaise, myalgia, nausea/vomiting, arthralgia and chills.

    Time frame: From dose 2 (Day 57) up to 7 days post-dose 2 (Day 64)

  3. Main Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 1

    An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Unsolicited AEs were events which were reported by the participant voluntarily or obtained by means of interviewing the participants in a nondirected manner.

    Time frame: From dose 1 (Day 1) up to 28 days post-dose 1 (Day 29)

  4. Main Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 2

    An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Unsolicited AEs were events which were reported by the participant voluntarily or obtained by means of interviewing the participant in a nondirected manner.

    Time frame: From dose 2 (Day 57) up to 28 days post-dose 2 (Day 85)

  5. Main Study: Percentage of Participants With Serious Adverse Events (SAEs) up to 6 Months Post Dose-2 on Day 57

    An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. A SAE is an adverse event resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.

    Time frame: Up to 6 months post dose-2 on Day 57 (Up to 8 months)

  6. Main Study: Percentage of Participants With SAEs Related to Study Intervention

    Percentage of participants with SAEs related to study intervention were reported. A SAE is an adverse event resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.

    Time frame: Up to Day 365

Secondary outcomes

  1. Main Study: Geometric Mean of Binding Antibody Levels Against the Ebola Virus Glycoprotein (EBOV GP)

    Geometric mean of binding antibody levels against the EBOV GP were reported.

    Time frame: 21 days post-dose 2 (Day 78)

07

Results

Posted Jun 22, 2023

Participant flow

Main Study: Up to Day 365
Participant flow — Main Study: Up to Day 365
MilestoneMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Extension Study: Ad26.ZEBOV + MVA-BN-Filo
Started75330
Completed72330
Not completed300
Withdrew: Withdrawal by parent/guardian200
Withdrew: Other100
Extension Study: Up to Extension Day 85
Participant flow — Extension Study: Up to Extension Day 85
MilestoneMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Extension Study: Ad26.ZEBOV + MVA-BN-Filo
Started0026
Completed0025
Not completed001
Withdrew: Adverse event001

Outcome measures

PrimaryMain Study: Percentage of Participants With Solicited Local and Systemic Adverse Events (AEs) up to 7 Days Post-dose 1

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Solicited local AEs that included injection site pain/tenderness, erythema, induration/swelling, itching at the vaccination site, were pre-defined local (at the injection site) AEs for which participant were specifically questioned and which were noted by participant in their diary for 7 days post vaccination. Solicited systemic events included fever, headache, fatigue/malaise, myalgia, nausea/vomiting, arthralgia and chills.

Time frame:
From dose 1 (Day 1) up to 7 days post-dose 1 (Day 8)
Reported as:
Number · Percentage of Participants
Main Study: Percentage of Participants With Solicited Local and Systemic Adverse Events (AEs) up to 7 Days Post-dose 1
Percentage of ParticipantsMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Solicited Local AEs14.76.1
Solicited Systemic AEs36.030.3
PrimaryMain Study: Percentage of Participants With Solicited Local and Systemic AEs up to 7 Days Post-dose 2

An AE is any untoward medical occurrence in a participants participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Solicited local AEs that included injection site pain/tenderness, erythema, induration/swelling, itching at the vaccination site, were pre-defined local (at the injection site) AEs for which participant were specifically questioned and which were noted by participant in their diary for 7 days post vaccination. Solicited systemic events included fever, headache, fatigue/malaise, myalgia, nausea/vomiting, arthralgia and chills.

Time frame:
From dose 2 (Day 57) up to 7 days post-dose 2 (Day 64)
Reported as:
Number · Percentage of Participants
Main Study: Percentage of Participants With Solicited Local and Systemic AEs up to 7 Days Post-dose 2
Percentage of ParticipantsMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Solicited Local AEs9.39.1
Solicited Systemic AEs29.333.3
PrimaryMain Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 1

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Unsolicited AEs were events which were reported by the participant voluntarily or obtained by means of interviewing the participants in a nondirected manner.

Time frame:
From dose 1 (Day 1) up to 28 days post-dose 1 (Day 29)
Reported as:
Number · Percentage of Participants
Main Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 1
Percentage of ParticipantsMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Main Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 161.366.7
PrimaryMain Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 2

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. Unsolicited AEs were events which were reported by the participant voluntarily or obtained by means of interviewing the participant in a nondirected manner.

Time frame:
From dose 2 (Day 57) up to 28 days post-dose 2 (Day 85)
Reported as:
Number · Percentage of Participants
Main Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 2
Percentage of ParticipantsMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Main Study: Percentage of Participants With Unsolicited AEs up to 28 Days Post-dose 257.372.7
PrimaryMain Study: Percentage of Participants With Serious Adverse Events (SAEs) up to 6 Months Post Dose-2 on Day 57

An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study. A SAE is an adverse event resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.

Time frame:
Up to 6 months post dose-2 on Day 57 (Up to 8 months)
Reported as:
Number · Percentage of Participants
Main Study: Percentage of Participants With Serious Adverse Events (SAEs) up to 6 Months Post Dose-2 on Day 57
Percentage of ParticipantsMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Main Study: Percentage of Participants With Serious Adverse Events (SAEs) up to 6 Months Post Dose-2 on Day 5713.312.1
SecondaryMain Study: Geometric Mean of Binding Antibody Levels Against the Ebola Virus Glycoprotein (EBOV GP)

Geometric mean of binding antibody levels against the EBOV GP were reported.

Time frame:
21 days post-dose 2 (Day 78)
Reported as:
Geometric mean · ELISA Units/milliliter (EU/mL)
Main Study: Geometric Mean of Binding Antibody Levels Against the Ebola Virus Glycoprotein (EBOV GP)
ELISA Units/milliliter (EU/mL)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Main Study: Geometric Mean of Binding Antibody Levels Against the Ebola Virus Glycoprotein (EBOV GP)24309 (19695 to 30005)NA (NA to NA)
PrimaryMain Study: Percentage of Participants With SAEs Related to Study Intervention

Percentage of participants with SAEs related to study intervention were reported. A SAE is an adverse event resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.

Time frame:
Up to Day 365
Reported as:
Number · Percentage of Participants
Main Study: Percentage of Participants With SAEs Related to Study Intervention
Percentage of ParticipantsMain Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)
Main Study: Percentage of Participants With SAEs Related to Study Intervention00

Adverse events

Collected over Main study: Up to Day 365 ; Extension study: Up to extension Day 85. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Main Study: Ad26.ZEBOV+MVA-BN-Filo+MenACWY0/75 (0%)10/75 (13.3%)58/75 (77.3%)
Main Study: MenACWY (Control Arm)0/33 (0%)4/33 (12.1%)26/33 (78.8%)
Extension Study: Ad26.ZEBOV+MVA-BN-Filo0/26 (0%)0/26 (0%)9/26 (34.6%)
Most frequent serious events
Showing 10 of 14
Most frequent serious events
EventMain Study: Ad26.ZEBOV+MVA-BN-Filo+MenACWYMain Study: MenACWY (Control Arm)Extension Study: Ad26.ZEBOV+MVA-BN-Filo
GastroenteritisInfections and infestations5/751/330/26
DiarrhoeaGastrointestinal disorders0/751/330/26
BronchiolitisInfections and infestations1/751/330/26
Gastrointestinal CandidiasisInfections and infestations0/751/330/26
MalariaInfections and infestations2/751/330/26
SepsisInfections and infestations0/751/330/26
Hypovolaemic ShockVascular disorders0/751/330/26
DehydrationMetabolism and nutrition disorders2/750/330/26
AnaemiaBlood and lymphatic system disorders1/750/330/26
VomitingGastrointestinal disorders1/750/330/26
Most frequent other events
Showing 10 of 18
Most frequent other events
EventMain Study: Ad26.ZEBOV+MVA-BN-Filo+MenACWYMain Study: MenACWY (Control Arm)Extension Study: Ad26.ZEBOV+MVA-BN-Filo
MalariaInfections and infestations13/759/336/26
Respiratory Tract InfectionInfections and infestations15/759/331/26
BronchitisInfections and infestations9/757/331/26
NasopharyngitisInfections and infestations12/756/330/26
Upper Respiratory Tract InfectionInfections and infestations8/756/333/26
RhinitisInfections and infestations10/755/330/26
AcarodermatitisInfections and infestations6/754/330/26
Helminthic InfectionInfections and infestations1/750/333/26
Oral CandidiasisInfections and infestations7/753/330/26
FuruncleInfections and infestations6/753/331/26

Baseline characteristics

Age, Continuous
Age, Continuous(months)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Total
Mean7.7 ± 2.517.5 ± 2.667.6 ± 2.55
Age, Customized
Age, Customized(Participants)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Total
4 to <= 8 months431962
>8 to 11 months321446
Sex: Female, Male
Sex: Female, Male(Participants)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Total
Female371350
Male382058
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Total
Hispanic or Latino000
Not Hispanic or Latino361955
Unknown or Not Reported391453
Race (NIH/OMB)
Race (NIH/OMB)(Participants)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Total
American Indian or Alaska Native000
Asian000
Native Hawaiian or Other Pacific Islander000
Black or African American361955
White000
More than one race000
Unknown or Not Reported391453
Region of Enrollment
Region of Enrollment(Participants)Main Study: Ad26.ZEBOV + MVA-BN-Filo + MenACWYMain Study: MenACWY (Control Arm)Total
Guinea391453
Sierra Leone361955
08

Study locations

2 sites
  • Centre National de Formation et de Recherche en Sante Rurale de Maferinyah
    Conakry, 2649, Guinea
  • College of Med and Allied Health Sciences, University of Sierra Leone
    Freetown, Sierra Leone
09

References and documents

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

10

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Aug 2019 to primary completion in Aug 2022, 36 months.

Results were first posted in Jun 2023, 10 months after primary completion. A results delay was requested in Dec 2021.

Of 13 phase 2 interventional studies under Hemorrhagic Fever, Ebola, half reached primary completion within 32 months of starting (the median), counting those still running; a quarter within 4 and three quarters within 39. This study's 36 months is above that.

How these figures are worked out, and which studies are left out of them.

Registered
Apr 25, 2019
First posted
Apr 29, 2019
StartActual
Aug 19, 2019
Primary completionActual
Aug 22, 2022
CompletionActual
Sep 28, 2022
Results delay requested
Dec 7, 2021
Results first posted
Jun 22, 2023
Last update
May 25, 2025
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on May 25, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT03929757
Lead sponsor
Janssen Vaccines & Prevention B.V.
Collaborators
London School of Hygiene and Tropical Medicine, University of Sierra Leone, Institut National de la Santé Et de la Recherche Médicale, France
Responsible party
Sponsor
First posted
Apr 29, 2019
Start date
Aug 19, 2019
Primary completion
Aug 22, 2022
Completion
Sep 28, 2022
Results posted
Jun 22, 2023
Last update
May 25, 2025

Study contacts

Janssen Vaccines & Prevention B.V. Clinical Trial
study director · Janssen Vaccines & Prevention B.V.

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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