New Smallpox and Mpox Vaccine Version Approved

With clade I mpox outbreaks occurring in hard-to-reach areas in Central and Eastern Africa, a new version of an effective vaccine has been approved.

Bavarian Nordic A/S announced that the U.S. Food and Drug Administration (FDA) has approved the freeze-dried formulation of the JYNNEOS® vaccine to prevent smallpox and mpox disease in adults 18 and older.

Announced on March 31, 2025, this FDA approval will enable additional flexibility for stockpiling against a smallpox event or mpox outbreak. 

The Company recently informed the African CDC that it can manufacture about ten million vaccine doses in addition to current orders by the end of 2025.

The current liquid-frozen formulation of JYNNEOS, approved by the FDA in September 2019, has specific cold-chain requirements, while the freeze-dried formulation provides advantages in terms of transportation, storage conditions, and shelf life, all of which are essential factors for long-term stockpiling. 

“Today’s FDA approval represents a significant milestone in our development of this next generation of JYNNEOS and in our collaborative efforts with the U.S. government to strengthen public health security,” said Paul Chaplin, President and CEO of Bavarian Nordic, in a press release.

“As a long-term supplier of JYNNEOS to the U.S. biological preparedness, we are committed to supporting the government’s efforts to protect its citizens against current and future public health threats.”

To alert international travelers of this continued health risk, the U.S. CDC maintains Level 2 Travel Health Advisories.

JYNNEOS, a two-dose vaccine based on a live, attenuated vaccinia virus, is commercially available in pharmacies and clinics in the United States.

Internationally, JYNNEOS is known as MVA-BN®, IMVAMUNE®, and IMVANEX®.