Safety and Immunogenicity of the Candidate Vaccine MVA-MERS-S_DF-1 Against MERS

A Two-center, Randomized, Double-blind, Placebo-controlled, Phase Ib Study to Assess the Safety, Tolerability and Immunogenicity of Two Ascending Doses of the Candidate Vaccine MVA-MERS-S_DF-1 in Healthy Study Subjects

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT04119440

Acronym

MVA-MERS-S

Enrollment

145

Registered

2019-10-08

Start date

2021-04-16

Completion date

2024-11-06

Last updated

2025-04-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

MERS (Middle East Respiratory Syndrome)

Keywords

MERS-CoV, CEPI, viral vector vaccine

Brief summary

The study will be a two center, randomized, double blind, placebo controlled study of the MVA MERS S\_DF-1 candidate delivered by i.m. injection. To evaluate the MERS-S-specific antibody responses and safety profile induced by the two dosage levels of MVA-MERS-S\_DF-1 the data will be compared to a placebo control group.

Detailed description

This will be a Phase Ib, two-center study in approximately 160 healthy adults aged 18-55 years The study is separated in two parts: Part A: The study starts with a single center open-label run-in phase of two dose levels (cohort 1 low dose: 2x10\^7 PFU, cohort 2 high dose: 2x10\^8 PFU) in 10 healthy subjects. 5 subjects will be allocated to each dose cohort and will receive immunization on day 0 and day 28. Part B: Two-center, randomized, double-blind, placebo-controlled, dose-finding study. This part is a double-blinded trial in approximately 150 healthy subjects. Subjects will be allocated to two different dose cohorts and a placebo cohort; each receiving three vaccine injections.

Interventions

BIOLOGICALMVA-MERS-S_DF1 - Low Dose

Administrations of the low dose via the intramuscular route

BIOLOGICALMVA-MERS-S_DF1 - High Dose

Administrations of the high dose via the intramuscular route

OTHERPlacebo

Administrations of placebo via the intramuscular route

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

TRIPLE (Subject, Investigator, Outcomes Assessor)

Masking description

Double-blinded

Intervention model description

Randomized, double-blinded with an open-label run-in Phase (Part A) Part A: Open-label Part B: Double-blind

Eligibility

Sex/Gender

ALL

Age

18 Years to 55 Years

Healthy volunteers

Yes

Inclusion criteria

1. Written informed consent form. 2. Healthy male and female subjects aged 18-55 years. 3. No clinically significant acute health problems as determined from medical history and physical examination at screening visit. 4. Body mass index 18.5 - 30.0 kg/m2 and weight \> 50 kg at screening. 5. Non-pregnant, non-lactating female with negative pregnancy test. 6. Males and females who agree to comply with the applicable contraceptive requirements of the protocol.

Exclusion criteria

1. Receipt of any vaccine from 2 weeks prior to each trial vac-cination (4 weeks for live vaccines) to 3 weeks after each trial vaccination. 2. Receipt of vaccination against MERS or MVA immunizations.in the medical history. 3. Known allergy to the components of the MVA-MERS-S\_DF-1 vaccine product. 4. Evidence in the subject's medical history or in the medical examination that might influence either the safety of the subject or the absorption, distribution, metabolism or excretion of the investigational product. 5. Any confirmed or suspected immunosuppressive or immuno-deficient condition, cytotoxic therapy in the previous 5 years, and/or diabetes. 6. Any chronic or active neurologic disorder, including seizures and epilepsy, excluding a single febrile seizure as a child.

Design outcomes

Primary

Measure	Time frame	Description
Frequency of adverse events associated with MVA-MERS-S_DF-1.	day 1, 14, 29, 42, 56, 84, 168, 336, 364	Safety and reactogenicity will be assesssed by observation, questionaire and diary. Changes from baseline for safety laboratory measures will be monitored. Occurence of SAE will be collected throughout the entire study duration.
Frequency and severity of local injection site reactogenicity signs and symptoms	day 1, 14, 29, 42, 84, 336	—

Secondary

Measure	Time frame	Description
Immunogenicity	day 0, 14, 28, 42, 56, 70, 84, 168, 336, 364 (dependent on vaccination scheme)	Magnitude of MERS-S-specific antibody re-sponses (ELISA and neutralization assays) monitored in a centralized approved laboratory

Countries

Germany, Netherlands

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 14, 2026