Mpox Vaccines

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Last reviewed
September 18, 2023
Content Overview
Mpox vaccines are approved and offered various countries in 2023.

Mpox Vaccines 2023

The United States (U.S.) began offering Bavarian Nordic's JYNNEOS® vaccine to healthcare staff in Boston on May 24, 2022, followed by mpox vaccination services in New York City and San Francisco. As of September 2023, over 1.2 million (1st and 2nd) JYNNEOS doses had been administered in U.S. Jurisdictions. On August 3, 2023, the U.S. government ordered an additional $120 million worth of JYNNEOS vaccines.

Mpox Vaccines

The U.S. FDA Approved the JYNNEOS® (MVA-BN, IMVANEX®, IMVAMUNE®) Smallpox and Mpox Vaccine, Live, Nonreplicating for the prevention of disease in adults on September 24, 2019. The European Medicines Agency (EMA) approved IMVANEX (Jynneos) in 2013 for preventing smallpox in the European Union (E.U.) and for mpox caused by vaccinia on July 27, 2022. The United Kingdom (U.K.) began offering IMVANEX® to specific mpox close contacts in England in May 2022. The U.K. Health Security Agency confirmed Jynneos doses remain available for gay, bisexual, and men who have sex with men at the highest risk from mpox in 2023. Mpox vaccination clinics are operational in London during 2023.

Japan's K.M. Biologics' LC16 "KMB" freeze-dried smallpox vaccine was approved as an additional indication for the prevention of the mpox virus by the Japanese Ministry of Health, Labor, and Welfare. In addition, the ACAM2000® live vaccinia virus vaccine is authorized to prevent mpox infections in various countries.

Mpox Vaccine Candidates 2023

BioNTech S.E. is initiating a Phase 1/2 clinical trial (BNT166-01) is evaluating the safety, tolerability, reactogenicity, and immunogenicity of investigational RNA-based multivalent vaccine candidates (BNT166a and BNT166c), up to three dose levels. The BNT166 vaccine candidates encode surface antigens expressed in the two infectious forms of the monkeypox virus (MPXV) to fight virus replication and infectivity efficiently. The study, launched in August 2023, is expected to enroll 96 people and be completed in May 2023. The Coalition for Epidemic Preparedness Innovations (CEPI) commits funding up to $90 million to develop BNT166 vaccine candidates.

Beijing Institute of Biological Products Co., Ltd. (BIBP), a subsidiary of China National Biotec Group Company Limited, China National Pharmaceutical Group Co., Ltd. (Sinopharm) confirmed China's drug authority granted permission to launch a mpox vaccine candidate based on replication-defective mpox viruses that cannot spread but can grant a person immunity.

Serum Institute of India, Reliance Life Sciences, and Dr Reddy's Laboratory are among a group of firms collaborating on producing a mpox virus protective vaccine in India. The Indian Council of Medical Research (ICMR) began this initiative on July 27, 2022: Collaboration for developing In-Vitro Diagnostic Kits and Vaccine candidates against the mpox virus.

Blue Water Vaccines Inc. and AbVacc, Inc. confirmed a joint development of vaccine candidates targeting mpox utilizing BWV's norovirus shell and protrusion ("S&P") virus-like particle platform, which allows for the presentation of multiple antigens on the surface of either the S or P particle of a norovirus backbone. Initial data show mice could generate an immune response following vaccination, and antibodies could neutralize the vaccinia virus.

Emergex Vaccines Holding Limited announced on October 18, 2022, that it has formulated and confirmed the synthesis and assembly of a CD8+ T cell Adaptive Vaccine for smallpox and mpox, comprised predominantly of early "eclipse phase" antigens.

Tonix Pharmaceuticals Holding Corp. TNX-8011 is a preclinical live virus vaccine candidate based on synthesized horsepox to protect people against mpox and smallpox. In addition, the U.S. Patent and Trademark Office issued a patent on May 31, 2022, entitled "Synthetic Chimeric Poxviruses." In July 2022, the Company announced a collaboration with the Kenya Medical Research Institute to seek regulatory approval for conducting a Phase 1 clinical study. On December 1, 2022, the Company presented the Live Virus Smallpox and Mpox Vaccine. On August 21, 2023, the Company announced FDA feedback provides a path to agreement on the design of a Phase 1/2 study and the overall clinical development plan.

EpiVax, Inc.'s "Epitope-Driven Vaccine" is a smallpox vaccine candidate predicted to be highly effective against mpox. The development of VennVax, a DNA-prime, peptide-boost multi-T-cell epitope poxvirus vaccine, was funded by the U.S. National Institutes of Health (SBIR grant #R43AI058376).

Blue Water Vaccines Inc. announced on August 17, 2022, plans to explore the potential to develop a novel mpox vaccine using its norovirus shell and protrusion virus-like particle platform. Blue Water Vaccines has an agreement with Cincinnati Children's Medical Center to develop vaccines.

Mpox Vaccinations U.S.

On August 9, 2022, the U.S. Food and Drug Administration (FDA) authorized the emergency use of an alternative dosing approach that allows healthcare providers to use the vaccine from one Jynneos vial to protect up to five people when administered intradermally to individuals 18 years of age or older. In September 2022, NYC Health began offering a second JYNNEOS® dose. As of February 8, 2023, the Assistant Secretary for Preparedness and Response (ASPR) confirmed it delivered about 857,000 vials of Jynneos vaccines in the U.S. The Jynneos vaccine is available at specific health clinics and pharmacies in the U.S.

The U.S. national Mpox vaccine strategy was also announced on June 28, 2022, which was updated by the U.S. Centers for Disease Control and Prevention (CDC) on February 6, 2023, continuing to recommend people exposed to the mpox virus and those more likely to contract the sexually transmitted disease should be vaccinated. On June 23, 2023, the CDC's Advisory Committee on Immunization Practices (ACIP) presented no recommendation for a third JYNNEOS dose, including for persons with advanced HIV or other severe immunocompromised. It's unknown how long JYNNEOS vaccine protection lasts or if protection might decrease over time, says the CDC. 

Mpox Vaccine Efficacy

Public Health France published an update on March 23, 2023, confirming multiple cases of mpox in previously vaccinated men in the Centre-Val de Loire region. The CDC posted data on December 8, 2022, suggesting the effectiveness of a single dose of JYNNEOS was 87% in people who received one dose subcutaneously (under the skin) and one dose by intradermal (into the skin) administration. The UKHSA's limited analysis on November 22, 2022, estimated that the effectiveness for a single dose was 78% fourteen or more days after the initial vaccination. On June 27, 2022, the WHO stated that decisions around immunization with smallpox or mpox vaccines (pre-emptive or post-exposure) should be by shared clinical decision-making, based on a joint assessment of risks and benefits, between a healthcare provider and prospective vaccinee, on a case-by-case basis. The journal Nature Medicine published a study on October 18, 2022 - Low levels of mpox virus neutralizing antibodies identified after MVA-BN vaccination in healthy individuals.

Mpox - Smallpox Vaccine Authorizations

Because the human mpox virus (hMPXV) has a double-stranded DNA genome of ~197 kb and is closely related to the virus that causes smallpox, research indicates the Maryland-based Emergent BioSolutions developed ACAM2000® smallpox vaccine may also protect people from mpox. According to the U.S. CDC, past data suggests that the ACAM2000 is about 85% effective in preventing a version of mpox. On August 2, 2022, the FDA confirmed ACAM2000 could be used against mpox under the FDA's Expanded Access Investigational New Drug (IND) mechanism, which requires informed consent and additional IND requirements. The journal Cell Host & Microbe published a study on April 25, 2023, that showed individuals born before 1976 and vaccinated with a smallpox vaccine had robust effector memory MPXV-specific T cell responses in mild mpox and long-lived TCF-1+ VACV/MPXV-specific CD8+ T cells decades after smallpox vaccination.

Mpox Alternative Vaccination

A CDC Morbidity and Mortality Weekly Report confirmed in July 2023 that the route of administration of the first dose of Bavarian Nordic JYNNEOS® (MVA-BN) vaccine was not associated with lower overall 2-dose series completion rates during the mpox outbreak in the U.S. The U.S. FDA issued an Emergency Use Authorization (EUA) on August 9, 2022, allowing healthcare providers to use an alternative dosing regimen of the JYNNEOS Vaccine to expand the total number of available doses by up to five-fold. In addition, the EUA now allows for 0.1ml of the JYNNEOS vaccine to be administered between layers of the skin (intradermal instead of 0.5ml of the vaccines administered under the skin (subcutaneously). The EMA's Emergency Task Force confirmed on August 19, 2022, that national authorities might decide as a temporary measure to use Imvanex as an intradermal injection at a lower dose to protect at-risk individuals during the current monkeypox outbreak. And the U.K. Health Security Agency confirmed on August 22, 2022, that it offers eligible patients smaller (fractional dosing ) but equally effective doses of the Jynneos / IMVANEX vaccine.

Mpox Vaccine Coadministration

The U.S. CDC says there is limited data on administering Jynneos vaccines simultaneously with other vaccines. However, there are additional considerations if administering Jynneos and a COVID-19 vaccine (Interim Clinical Considerations). And people, particularly young adult males, might consider waiting four weeks after Jynneos or ACAM2000 vaccination before receiving a Moderna, Novavax, or Pfizer-BioNTech COVID-19 vaccine because of the observed risk for myocarditis and/or pericarditis after receipt of ACAM2000 and mRNA vaccines, and the unknown heart health after Jynneos vaccination.

Mpox Vaccines For Children

On August 22, 2022, the U.S. CDC confirmed children and adolescents with exposure to people with suspected or confirmed mpox infections may be eligible for post-exposure prophylaxis with vaccination, immune globulin, or antiviral medication based on shared decision-making, as there is no clinical efficacy data available.

Mpox Vaccine For Nurses

The U.S. CDC published: Health Care Personnel Exposures to Subsequently Laboratory-Confirmed Mpox Patients — Colorado, 2022, and the U.K. HSA published Guidance, Mpox: waiting for your vaccination, on September 6, 2022. Previously, Alison Shely, DNP, FNP-C, wrote an article on August 31, 2022: What Nurses Need to Know About Mpox. Then, on October 17, 2022, the CDC published a report that describes the first occupationally acquired Mpox infection in a U.S. healthcare worker during the 2022 outbreak. 

Mpox Virus Disease

Monkeypox is a viral zoonotic virus that is transmitted from one person to another by physical contact with lesions, body fluids, respiratory droplets, and contaminated materials. The monkeypox virus causes monkeypox disease, a member of the Orthopoxvirus genus in the family Poxviridae. According to the WHO, the monkeypox virus has two distinct genetic clades: the Congo Basin and WesAfrican

Mpox Outbreak News

Mpox outbreak news was updated in August 2023. And other sexually transmitted disease vaccine news is posted at this link.