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JYNNEOS
JYNNEOS is a live attenuated vaccinia virus vaccine that stimulates immune responses against orthopoxviruses including monkeypox and smallpox.
JYNNEOS is a live attenuated vaccinia virus vaccine that stimulates immune responses against orthopoxviruses including monkeypox and smallpox. Used for Prevention of monkeypox (mpox) in adults 18 years and older at risk of exposure, Prevention of smallpox in adults 18 years and older at risk of exposure.
At a glance
| Generic name | JYNNEOS |
|---|---|
| Sponsor | Womack Army Medical Center |
| Drug class | Live attenuated viral vaccine |
| Target | Orthopoxvirus antigens (vaccinia virus envelope and core proteins) |
| Modality | Biologic |
| Therapeutic area | Immunology / Infectious Disease |
| Phase | FDA-approved |
Mechanism of action
JYNNEOS contains a modified vaccinia Ankara (MVA) virus strain that has been attenuated through serial passage in cell culture, making it non-replicating in human cells while retaining immunogenicity. The vaccine triggers both cellular and humoral immune responses by expressing orthopoxvirus antigens, providing protection against monkeypox and smallpox without the safety concerns of older replicating smallpox vaccines.
Approved indications
- Prevention of monkeypox (mpox) in adults 18 years and older at risk of exposure
- Prevention of smallpox in adults 18 years and older at risk of exposure
Common side effects
- Injection site erythema
- Injection site swelling
- Myalgia
- Fatigue
- Headache
- Fever
Key clinical trials
- A Phase 2 Randomized Multisite Trial to Inform Public Health Strategies Involving the Use of MVA-BN Vaccine for Mpox (PHASE2)
- Assessment of Safety Profile of MVA-BN Vaccine in the PALM-007 Study in DRC (PHASE4)
- Comparability Trial of the MVA-BN Vaccine Manufactured in Different Production Cells (PHASE2)
- Evaluating the Human Immune Response to the JYNNEOS Vaccine (EARLY_PHASE1)
- Study to Assess the Safety and Immunogenicity of TPOXX® When Administered Orally for 28 Days With JYNNEOS (PHASE2)
- JYNNEOS Smallpox Vaccine in Adult Healthcare Personnel at Risk for Mpox in the Democratic Republic of the Congo (PHASE3)
- Trial to Evaluate the Immunogenicity of Dose Reduction Strategies of the MVA-BN Monkeypox Vaccine (PHASE2)
- Assessment of Metformin for Restoration of Immune Homeostasis in HIV+ and HIV- Individuals With a History of Injection Drug Use (PHASE4)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- JYNNEOS CI brief — competitive landscape report
- JYNNEOS updates RSS · CI watch RSS
- Womack Army Medical Center portfolio CI