This phase 2 clinical trial study evaluates the persistence of antibodies following vaccination with MVA-BN and assesses the immunological memory response induced by a booster vaccination with MVA-BN in subjects two years after their participation in trial POX-MVA-005 (NCT00316524) in which they had received one or two doses of MVA-BN.
MedRxiv published the non-peer-reviewed clinical trial results on September 7, 2022.
They concluded priming with either 1 or 2 doses of MVA-BN induced a durable immune memory, similar to that of older generation replicating smallpox vaccines. When the MVA-BN vaccine was administered as a booster to individuals either primed 2 years earlier with MVA-BN or an older generation replicating smallpox vaccine in the distant past, it elicited a similar rapid and durable immune response that was generally safe and well-tolerated. A one-dose priming with MVA induced a long-term B-cell memory that resulted in robust anamnestic responses following an MVA booster 2 years later, suggesting that a single dose may offer protection against future exposure.