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Smallpox and Mpox Vaccine
This vaccine stimulates the immune system to recognize and respond to smallpox and mpox viruses by presenting viral antigens.
This vaccine stimulates the immune system to recognize and respond to smallpox and mpox viruses by presenting viral antigens. Used for Smallpox prevention and post-exposure prophylaxis, Mpox (monkeypox) prevention and post-exposure prophylaxis.
At a glance
| Generic name | Smallpox and Mpox Vaccine |
|---|---|
| Also known as | JYNNEOS |
| Sponsor | SIGA Technologies |
| Drug class | Live attenuated viral vaccine / Recombinant viral vaccine |
| Modality | Small molecule |
| Therapeutic area | Immunology / Infectious Disease |
| Phase | FDA-approved |
Mechanism of action
The vaccine contains live attenuated vaccinia virus (ACAM2000) or recombinant vaccinia virus (JYNNEOS/Imvanex), which triggers both cellular and humoral immune responses against orthopoxviruses. This generates protective antibodies and T-cell immunity that prevent infection or reduce disease severity upon exposure to smallpox or mpox.
Approved indications
- Smallpox prevention and post-exposure prophylaxis
- Mpox (monkeypox) prevention and post-exposure prophylaxis
Common side effects
- Injection site reaction (erythema, induration, pain)
- Fever
- Myalgia
- Fatigue
- Headache
Key clinical trials
- A Phase 2 Randomized Multisite Trial to Inform Public Health Strategies Involving the Use of MVA-BN Vaccine for Mpox (PHASE2)
- Prospective Study for the FOLLOW-UP of Human Monkeypox Cases and Smallpox Vaccinees at Risk
- Phase 3 Maternal Safety & Immunogenicity Trial of MVA-BN® in DRC (PHASE3)
- Evaluate the Safety and Immunogenicity of the MVA-SIBP Vaccine in the Democratic Republic of the Congo (PHASE2)
- Open-label, Multicenter Immunogenicity and Safety Study of MVA-BN Vaccine in Children From 2 Years to Less Than 12 Years of Age Compared to Adults for the Prevention of Smallpox, Mpox, and Related Orthopoxvirus Infections (PHASE2)
- Evaluation of Effectiveness and Safety of LC16m8 Mpox Vaccine in the Democratic Republic of Congo (DRC)
- Efficacy/Effectiveness, Safety, and Immunogenicity of LC16m8 Mpox Vaccine in Colombia (PHASE3)
- Phase 3 Infant Safety & Immunogenicity Trial of MVA-BN® in DRC (PHASE3)
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:
- Smallpox and Mpox Vaccine CI brief — competitive landscape report
- Smallpox and Mpox Vaccine updates RSS · CI watch RSS
- SIGA Technologies portfolio CI