CI

At a glance

ClinicalIndex Comparison Record
Phase 2Completed· 229 enrolled
Drug / intervention
JYNNEOSbiological
Likely dose
JYNNEOS 0.5 mLfrom record
Structured eligibility isn't available for this trial yet — see the full criteria in the Eligibility tab below.

Standardized by ClinicalIndex from the ClinicalTrials.gov record · verify against the source.

Search/NCT05512949
NCT05512949Phase 2Completed

A Phase 2 Randomized, Open-Label, Multisite Trial to Evaluate the Immunogenicity of Dose Reduction Strategies of the MVA-BN Vaccine

National Institute of Allergy and Infectious Diseases (NIAID)·interventional·Posted Aug 23, 2022·Updated Apr 16, 2026

In Brief

A Phase 2 clinical trial evaluating JYNNEOS for Monkeypox. Completed, enrolled 229 participants across 8 sites.

Detailed Summary

This study is a Phase 2 randomized, open-label, non-placebo controlled, multi-site clinical trial that will evaluate two intradermal (ID) regimens for Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN) vaccine compared to the standard subcutaneous (SC) regimen in healthy, vaccinia-naïve adults 18 to 50 years of age, inclusive. At least 210 participants will be enrolled and randomized to one of three study arms. The two dose sparing strategies include one-fifth (2 x 10\^7) and one-tenth (1 x 10\^7) of the standard dose of MVA-BN administered ID on Day 1 and 29 (Arm 1 and 2, respectively). The comparator arm (Arm 3) will be the 2-dose standard (1 x 10\^8) MVA-BN SC regimen. The study will enroll a 1:1:1 randomization allocation. Participants will not be stratified by clinical trial site, demographic characteristics or human immunodeficiency virus (HIV) infection status; however, these data will be collected during screening and enrollment. Each participant may be screened either in a separate visit in the 7 days prior to Day 1 or on Day 1. The primary hypothesis involves a two-step hierarchical process. The study will first test non-inferiority of the 2 x 10\^7 ID regimen relative to 1 x 10\^8 SC (standard dose regimen). If the 2 x 10\^7 ID regimen is non-inferior to the standard dose regimen, hypothesis testing will proceed to test non-inferiority of the 1 x 10\^7 ID regimen relative to the standard dose regimen. The primary objectives are: 1) to determine if peak humoral immune responses following an ID regimen of 2 x 10\^7 50% Tissue Culture Infectious Dose (TCID50) MVA-BN are non-inferior to the licensed regimen of 1 x 10\^8 MVA-BN administered SC; 2) to determine if peak humoral immune responses following an ID regimen of 1 x 10\^7 TCID50 MVA-BN are non-inferior to the licensed regimen of 1 x 10\^8 MVA-BN administered SC.

Study Details

Study Typeinterventional
Allocation--
Masking--
Primary Purpose--
ConditionsMonkeypox
CountriesUnited States
Collaborators--

Timeline

Phase 2CompletedFinished
2023202420252026
First PostedAug 23, 2022
Enrollment StartSep 9, 2022
Primary CompletionOct 12, 2023
Study CompletionFeb 24, 2025
TodayJul 2, 2026
Enrollment to primary: 1.1 yearsPosted 3.9 years ago

Interventions

JYNNEOSbiological

JYNNEOS is FDA-approved and licensed as a smallpox and monkeypox vaccine in the United States. JYNNEOS is a live vaccine produced from the strain Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN), an attenuated, non-replicating orthopoxvirus. Each 0.5 mL dose is formulated to contain 0.5 x 10\^8 to 3.95 x 10\^8 infectious units of MVA-BN live virus in 10 mM Tris (tromethamine), 140 mM sodium chloride at pH 7.7. Subcutaneous is administered in the deltoid region, intradermal is administered in the volar aspect (inner side) of the forearm.