FDA Authorizes Intradermal Use of Jynneos to Increase Supply During Monkeypox Outbreak

Under the EUA, Jynneos can be administered either intradermally for individuals aged ≥18 years or subcutaneously for individuals aged

The Food and Drug Administration (FDA) has granted emergency use authorization (EUA) for the Jynneos vaccine (smallpox and monkeypox vaccine, live, non-replicating) to allow for intradermal injection in individuals 18 years of age and older and subcutaneous injection in individuals less than 18 years of age who are determined to be at high risk for monkeypox infection.

Jynneos is a live vaccine produced from the strain Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN), an attenuated, non-replicating orthopoxvirus; this modified form of the vaccinia virus does not cause disease in humans and cannot reproduce in human cells. The vaccine received FDA approval in 2019 for subcutaneous administration in adults 18 years of age and older determined to be at high risk for smallpox or monkeypox infection.

Under the EUA, Jynneos is administered as 2 doses, 4 weeks (28 days) apart by intradermal injection (each dose is 0.1mL) for individuals 18 years of age and older or by subcutaneous injection (each dose is 0.5mL) for individuals younger than 18 years of age. As intradermal administration requires less vaccine per dose, the authorization will help increase supply of the vaccine during the 2022 monkeypox outbreak.

The EUA is supported by data from a 2015 clinical study of Jynneos, which evaluated a 2-dose series administered intradermally compared with subcutaneously. Results showed a similar immune response between the intradermal and subcutaneous treatment arms. Individuals who received intradermal administration reported a higher rate of injection site reactions (eg, redness, firmness, itchiness, swelling), but less pain, with manageable side effects. The FDA has determined that the known and potential benefits of Jynneos outweigh the known and potential risks for the authorized uses.

Additionally, subcutaneous administration of Jynneos in individuals younger than 18 years of age is supported by available safety and immune response data in adults, along with historical data with use of live vaccinia virus smallpox vaccine in pediatric populations.

“In recent weeks the monkeypox virus has continued to spread at a rate that has made it clear our current vaccine supply will not meet the current demand,” said FDA Commissioner Robert M. Califf, MD. “The FDA quickly explored other scientifically appropriate options to facilitate access to the vaccine for all impacted individuals. By increasing the number of available doses, more individuals who want to be vaccinated against monkeypox will now have the opportunity to do so.”

The Jynneos vaccine is supplied in 0.5mL vials. Each vial contains a single dose (0.5mL) for subcutaneous injection in individuals less than 18 years of age or up to 5 doses (0.1mL each) for intradermal injection in individuals 18 years of age and older.


  1. Monkeypox update: FDA authorizes emergency use of Jynneos vaccine to increase vaccine supply. News release. US Food and Drug Administration. August 9, 2022. Accessed August 10, 2022. https://www.prnewswire.com/news-releases/monkeypox-update-fda-authorizes-emergency-use-of-jynneos-vaccine-to-increase-vaccine-supply-301602903.html
  2. Fact sheet for healthcare providers administering vaccine: Emergency Use Authorization for Jynneos. https://www.fda.gov/media/160774/download. Accessed August 10, 2022.